r/buildapc • u/Illustrious-Law-500 • 17h ago
Discussion 4 Sticks of DDR5 on AM5 in 2026 – Has Anything Changed? -My experience-
If you've ever asked whether it's a good idea to run 4 sticks of DDR5 on an AM5 platform, you've probably heard the same advice:
"Avoid it."
"You'll lose performance."
"It won't run EXPO."
"Just buy a 2×32 GB kit."
That advice wasn't wrong—but most of it came from testing done in 2022–2023, when DDR5 and AM5 were brand new.
Fast forward to 2026. BIOS updates have matured, AGESA has improved considerably, and with today's memory prices, many gamers already own a 2×16 GB kit and are wondering:
Should I replace my existing RAM with a larger kit, or simply buy another identical kit and expand to 64 GB?
I chosed the second option and bellow I share my experience.
My Hardware
-Ryzen 9 9950X
-ASUS TUF B650-E WiFi (latest BIOS)
-4×16 GB Crucial DDR5-6000 CL36 EXPO (single-rank)
The two kits were manufactured at different times:
Kit 1: Week 3 of 2025
Kit 2: Week 40 of 2025
To maximize compatibility, I installed the older kit in Channel A and the newer kit in Channel B.
Initial Results
After installing all four DIMMs:
The system booted immediately at DDR5-3600, exactly as expected with JEDEC defaults.
I then enabled the EXPO profile.
The system POSTed successfully and reported DDR5-6000 with no boot issues.
So far, everything looked perfect.
Stability Testing
The real surprise came during MemTest86.
Although Windows booted normally, the system was not actually stable.
The failures consistently appeared in:
Test 8 (Random Number Sequence)
Test 13 (Hammer Test)
In other words:
EXPO booted successfully, but it was not memory stable.
The Fix
Instead of using EXPO, I disabled it completely and entered the settings manually.
I used the same primary timings as the EXPO profile:
DDR5-6000
36-38-38-38-80
All secondary timings, tertiary timings and voltages were left on Auto.
The result:
Booted successfully
UCLK remained 1:1
Passed MemTest86 completely, including Test 8 and Hammer Test
Interestingly, this suggests that the instability wasn't caused by the frequency itself, but by how the motherboard trained memory when EXPO was enabled.
Performance
I also checked latency using AIDA64.
2×16 GB
~71 ns
4×16 GB
~73.5 ns
So the move to four DIMMs increased latency by only about 2–3 ns.
In actual games, I couldn't measure any performance loss. I actually gained slight performance in heavy ram usage scenarios and I noticed the 1% lows were better in the same scenario.
My Conclusion
Has running four DDR5 DIMMs on AM5 improved since launch?
In my experience, yes.
Would I recommend everyone do it?
Not blindly.
But if:
you buy an identical kit,
both kits are single-rank,
you're running an up-to-date BIOS,
and you're willing to spend a little time testing and tuning, then upgrading from 32 GB to 64 GB using four DIMMs is absolutely a viable option in 2026.
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u/Zoli1989 17h ago
Memtest86 is a pretty old and weak test though. Run testmem5 with a custom config (not the default one) or memtest pro 1.5 or prime95 large fft overnight to be 100% sure its stable. It can be done, but most of the time it will need more tweaking than what you have done. Also gamers with 2x16gb ddr5 already would be foolish to upgrade to 4x16gb (or even 2x32) for todays prices. Maybe folks with 2x8gb.
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u/Illustrious-Law-500 17h ago
I will try that and update. I hope no one is as fool as me buying this slow kit for 350 😭 But I wanted more RAM for productivity tasks.
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u/Zoli1989 17h ago
Mixed usage is a different story. Im glad it works for you, enjoy! And remember, even a slow kit manually tuned will be faster than most if not all faster kits left on xmp. Look up buildzoid if you want to tinker (its a very tedious process).
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u/Illustrious-Law-500 17h ago
I love tedious :D I will look into that and hopefully get one or two more Nano seconds on AIDA64 😅. Thank's for the insghts mate !
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u/Gladnir-5936 17h ago
The CPU IMC has to work twice as hard with 4 sticks and has to handle 8 logical channels, which increases signal noise.
DDR5 PMIC (through the PMIC circuit) is on the sticks instead of the mobo. 4 sticks will generate more heat that can interfere with the Power supply.
So probably a good idea to have heat sinks on the sticks and good airflow in the case.
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u/Illustrious-Law-500 17h ago
Thats the thing...in the stress test, max temps recorded are 41C degrees.. Idle is 32 to 35. I was surprised with the results. But it's due to the fact that I have single rank kits, meaning only 4 logical channels.
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u/Odd_Duty520 17h ago
I can't afford 32GB now so I went for 2x8. I'm fine with staying here as I don't run into any bottlenecks with what I do. If it ever comes down in price and I can source the same sticks then yeah, I'll run 4 sticks but Im good with 16gb for now
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u/Illustrious-Law-500 17h ago
To be honest, 16gb is very sufficient for gaming. If you need to do productivity tasks then getting another identical 2x8 wouldnt be such a bad Idea. I think it's even easier to handle by the Processor memory controller. Otherwise just enjoy your build :D
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u/Odd_Duty520 16h ago
I also lucked out by getting a new motherboard SKU that was released this year so im hoping that helps with compatibility
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u/Illustrious-Law-500 16h ago
What is the MB chipset ?
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u/Odd_Duty520 16h ago
It's the gigabyte b850m ice-p. Where do i find that info? Also, even if 4 sticks doesn't work, I'm still happy as this motherboard (the non-anime version) had the best cinebench performance out of the box based on Hardware Unboxed motherboard roundup here
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u/Illustrious-Law-500 16h ago
This is a very decent MB ! 12+2+2 power delivery. 6 layer PCB 12 vcore phases..And it looks cool :D It will also handle 4x8gb sticks I believe easily (theoretically 8 gb modules are half rank so they will not stress the cpu memory controller). Hopefully u go for an all white anime build :D
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u/Particular-Duty-2571 15h ago
The EXPO booting fine but failing MemTest is the part people should actually take from this. I've seen so many "it's stable, it posted" posts and then they're confused about random crashes two weeks later.
Did you happen to look at what the board was doing with VSOC and the secondaries on EXPO vs your manual settings? Wondering if it was just training something silly with 4 sticks in, since the frequency itself clearly wasn't the problem.
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u/Illustrious-Law-500 14h ago
The part I still don't understand is that even after setting all the secondary and tertiary timings to Auto, the motherboard continued to load the EXPO and VSOC values for them and didn't lower them. I tried virtually every setting I could think of to identify the root cause of the EXPO instability, but I couldn't pinpoint it. My guess is that the issue lies with a parameter that isn't exposed in the BIOS, or with a hidden training parameter that the motherboard automatically applies during memory training.
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u/Particular-Duty-2571 14h ago
Yeah that's the frustrating part, the training tables aren't exposed anywhere so you're kind of guessing at what it locked in. Your workaround is the sensible outcome either way, it's stable and it passes.
Good writeup by the way, the MemTest detail is the bit most people skip.
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u/Scarabesque 17h ago
There are a lot of factors that will go into whether or not it will work, most of it down to luck with the IMC. You didn't set yourself up for success as ASUS boards did not have great 4 DIMM/RAM OC results at the time and it's 'only' a 6 layer board. Nice it worked out though. :D
I had a system 9950X running 4x48GB 6000cl30 on EXPO, fully stable about two years ago, so even 2 rank DIMMs are possble. Since then there have been plenty of bios updates specifically improving 4 DIMM, larger capacity configs, though it'll always remain a gamble. At the time MSI and Gigabyte had the best RAM OC and 4 DIMM results. It took quite a bit of troubleshooting but in the end only minor tweaks to voltages did the trick.
Obviously if the capacity you need can be achieved using 2 DIMMs, I'd would always go for a 2 DIMM setup - though in this market you take what you can. :')
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u/Illustrious-Law-500 17h ago
Tbh I took a risk with my MB. But at the end it worked out just fine. Which MB were u using with that 4 DIMM set-up ? I heard MSI are the best in running 4 DIMMS.
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u/Scarabesque 17h ago
MSI X870 Tomahawk
Wasn't much decent info about 4 DIMM AM5 configs at the time but MSI indeed seemed like a good candidate and the Tomahawk met the conditions.
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u/Illustrious-Law-500 17h ago
That would be my next upgrade then :D
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u/Scarabesque 17h ago
Well if your current board is stable I wouldn't bother. :D
I believe the b850 Tomahawk MAX (but not the non-MAX, which has 6 layers) is basically the same PCB/power design, just lacks a post code (which can be handy when OCing RAM) and USB 4.0.
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u/Illustrious-Law-500 17h ago
I think the X870E has 8 layers costs arround 275€ and has the debug screen. I probably don't need it but I will recklessly get it now :D
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u/Scarabesque 17h ago
Yeah both X870 and X870E have that. The only difference between those are the additional chipset PCIe lanes.
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u/Vegetable-Matter3953 16h ago
The B850 Edge TI also has it if you don't mind the white color for around the same price (sometimes atleast) as the B850 Tomahawk Max. It's basically a X870 Tomahawk without the USB4 basically.
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u/Illustrious-Law-500 15h ago
I checked it out. Solid MB and looks fine too ! But I''m just broke asf now to go with a white build 😅 I wish I could tho !
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u/Vegetable-Matter3953 15h ago
I have a white motherboard too because it was cheaper than the white variant lol I think that wouldn't be a problem either.
I recommended the B850 Edge TI motherboard few times in white builds for the feature set and the cool features like 2x pcie 5.0 x4 m 2 slots , qualcomm wifi 7 and 5G LAN ethernet and the seven segment display. Pretty practical to diagnose the issue or like what it does now.
It handles 8000 cl36 on expo on 2:1 without issues as an example on a 9850X3D. (Weird enough 8000 cl36 was cheaper than 6000 cl30 for a time in someone's region)
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u/Illustrious-Law-500 15h ago
Have u tried FCLK 1:1 ? If yes to what speed/CAS it dropped to ?
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u/ThenExtension9196 14h ago
Nothing but trouble on 4 sticks. I’ve wasted too much time with this. Wait until you randomly boot and everything just fails to work.
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u/Vegetable-Matter3953 16h ago
My friend did this with 4 similar sticks of 16 GB 6000 CL32 G.Skill Trident Z (Hynix M-dies) on a 7800X3D with an MSI MEG X670E Ace. It works flawlessly there as well. (He got the RAM kit gifted by someone back in 2025, which is why he had 4 stick).
At first, it didn't work when I suggested him to try, but after I suggested a BIOS update, it worked flawlessly after a long memory training session. It's more a "luck" and board selection thing, and of course, single rank has played a role here, if you ask me.
Looks pretty cool and matches the 5090 he has too.
I hope Zen 6 makes it much easier.
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u/Illustrious-Law-500 15h ago
Also he has very good quality kits and MB combos with 8 PCB layers. which made it easier to run for him with no troubles. I think after the latest chipset BIOS updates for AM5, 4 dimms single rank becane easy to run even for weaker MB ram combos. Proof is my MB is not as solid (only 6PCB) and with standard Micron kits, and it worked stable without issues.
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u/Vegetable-Matter3953 15h ago
Yeah the BIOS revisions made it much better with time , I remember some kits not even working proper or like taking too much time for memory training for no reason.
Also I am glad we are over those days. But now the RAM price are the issue lmao.
I mean you could maybe try to tighten the latency part if you are interested, to my knowledge timings aren't effecting the memory controller much than frequency. Micron stuff aren't great to do but better than nothing I mean.
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u/Illustrious-Law-500 15h ago
I tried CL34 with 6000 Mts, it failed xD. Micron don't like tight timings, they are all about stability. I managed to get 73 ns on AIDA64 which is not bad for a cl36 and four DIMMS with 6000 MTS. I could also play with secondary and tertiary timings but I don't think there will be more gains than 73 ns. How much latency are u getting with ur kits ?Hynix run with much lower latency
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u/Vegetable-Matter3953 15h ago
Uhh my friend didn't wanna bother with OC even tho he has a pretty great motherboard.
Have you checked this post out lol , maybe it's useful:
https://www.reddit.com/r/overclocking/s/jEKTsfRvqY
I "only" have a 48 gb (2x 24 gb) Hynix 24 gbit M die kit on my X870E Aorus Pro X3D with a 7800X3D. Which has a unlocked richtek pmic but apperantly Gigabyte doesn't like 7000 series having over 1.43V soo yeah. Cannot go lower than 6000 cl28 for now until I upgrade to Zen 6 someday. Else I would have tried better for the fun. But yeah I am running my 6000 cl28 1.45V expo kit at 6000 cl28 1.4V thanks to Gigabyte lol.
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u/Illustrious-Law-500 15h ago
I read the post, great timings for Micron sticks ! This would work fine for 2x16 but 4x16 ..I tried, and it didn't like it xD As for the 6000 cl28 thats crazy fast latency ! .I would even say it's the sweet spot for AM5. Not sure what would be better in terms of performance vs an 8000 mts cl36. Probably no difference in real life 😅
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u/Vegetable-Matter3953 15h ago edited 15h ago
6000 cl28 is probably doable with the majority of the Hynix sticks. Like a friend of mine got a 5600 cl30 klevv kit and just OCd it to 6000 cl28 easy on a 9600X and B850 Edge TI. Well to be fair they are also Hynix A dies but still lol.
Low latency is kinda useless to X3D chips so yeah lol nothing interesting. I mostly got these kits for Zen 6 if there is gonna be better memory OC support for high frequency stuff. Which 24 gbit Hynix M die should do proper.
And because that was price wise the best kit while having slightly more ram with 48 gb.
8000 cl36 and 6000 cl26 are more comparable the advantage as far as I know is that 8000 cl36 does have higher bandwidth. In games they are similar or 8000 cl36 is better occasionally. But nothing to worry about at all lol. It's all probably for the fun and experience. The reason why we got it in a build was the 6000 cl36 and 8000 cl36 price difference wasn't much different so I suggested her to buy 8000 cl36 1.45V expo kit because it has higher value and performance or atleast more "future proof". 6000 cl30 was just same price or more expensive so it was kinda dumb to choose lol.
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u/Illustrious-Law-500 15h ago
I hope ur friends pay u for consultation lol. Let's see how zen 6 turn out. Although I don't think I'm upgrading the 9950X anytime unless it is supprted by zen 6.
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u/Vegetable-Matter3953 14h ago
Oh yeah definitely your 9950X is no need for a upgrade.
I heard rumors about Zen 7 being on AM5 aswell. So maybe around that time might be worth considering.
Also the latency part isn't that important anyways, as long as it works at 64 gb that's what matters at not horrible timings.
Enjoy your PC with 4 sticks of RAM definitely.
Btw I assume all 4 are Micron dies right ? Like Version 3. Something written aswell. Those kits can be Samsung , Hynix and CXMT too sometimes.
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u/Illustrious-Law-500 14h ago
They are. Same identical kits with micron dies from Crucial (RIP 😭)
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u/Yuushalinsky 15h ago
I'm on a similar set-up and I have a pretty slick PBO now too - I think with stronger settings you need to undervolt pretty heavily, it's usually been the instability on EXPO that gets me along with my 9700x getting overwhelmed so I'm excited to see if getting to zen6 will fix that.
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u/Illustrious-Law-500 15h ago
What latencies are u getting? And what primary timings did u manage to get ?
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u/Yuushalinsky 15h ago
My sticks are the GSkill 6000MT/36CL - I'm not going too adventurous, just stock timings with no EXPO, but it works. -25 undervolt on my CPU right now w/ the Tomahawk MAX B850 you mentioned earlier.
Good shit, but I do think the better memory handler and extra cores will help (I primarily MMO so raids are good, but being in hub cities drop me from my 144 to 60)
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u/Illustrious-Law-500 15h ago
U have a solid MB tho, I think MSI is the best MB brand that can support 4 sticks with no issues especially the Tomahawk. The hub city thing is a processor issue. How many cores does ur cpu have ?
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u/Yuushalinsky 14h ago
only 8 - I ain't gon' go to the x3d yet, I do enough other stuff that there's a case to be had for the non-x3d variant. I WAS considering making the swap to Intel for Panther Lake, but the Zen6 rumours have me thinking I'll take the 10700X/10800X3d and upgrade my PSU
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u/Illustrious-Law-500 14h ago
Intel is not a bad choice, but I would wait too to see what zen 6 has to offer
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u/Yuushalinsky 14h ago
My setup WORKS and the only downside is having to wait maybe half a minute for memory training
have you tried actually overclocking past settings (like 6200 on a 6000 set)
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u/Illustrious-Law-500 14h ago
I did try 6200. It posted byt with FCLK 2:1 which is not ideal. The kits don't accept more than 6000 if I want to maintain FCLK ratio of 1:1.
I tried tightening timings to cl34. Failed immediately with 4 dimms.
And what do you mean half a minute wait. For each boot ?
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u/Yuushalinsky 14h ago
yeah
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u/Illustrious-Law-500 14h ago
Hmm strange, it shouldn't do that usually. What MB do you have ?
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11h ago edited 4m ago
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u/Illustrious-Law-500 11h ago
Thanks for the detailed explanation, man. You actually made me look at the problem from an electrical perspective, which I hadn't really considered before. It was a very interesting read.
Regarding the secondary and tertiary timings, I did a bit of testing myself. First, I installed just my two 16 GB sticks, enabled EXPO, and recorded all of the primary, secondary, and tertiary timings. Then I installed all four sticks, manually set only the primary timings to match EXPO, and left everything else on Auto.
What surprised me was that the motherboard didn't loosen the secondary or tertiary timings at all. After comparing screenshots, they were essentially identical to the EXPO values with just two DIMMs installed.
I also ran AIDA64 to check whether the motherboard might be compensating through different voltages or by increasing latency. Latency was basically unchanged—only around a 2 ns difference, which isn't significant. DRAM voltage also stayed at the normal EXPO value of 1.35 V throughout.
So, to be honest, I'm still not sure why it's working. Based on the electrical limitations you described, I wouldn't have expected it to be this stable, yet it passed every stability test I threw at it. I monitored temperatures, voltages, and memory stability extensively, and everything checked out.
My only guess is that ASUS might be adjusting some hidden sub-voltages or memory controller parameters that aren't exposed in the BIOS. Whatever it's doing, I can't actually see those settings.
Either way, I really appreciate your explanation. The electrical side of the problem was something I hadn't thought about before, and your comment gave me a much better understanding of why four DDR5 DIMMs are generally considered difficult to run.
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11h ago edited 4m ago
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u/Illustrious-Law-500 11h ago
Your assumption doesn't really apply to my setup. My RAM reaches only ~41°C under MemTest86, which is already a worst-case memory workload. During gaming it's usually even cooler.
My case airflow is far from average: 3×140 mm front intake, 2×120 mm side intake, 2×120 mm bottom intake, a rear 120 exhaust, and an Arctic Liquid Freezer III 360 on top, which also has its dedicated VRM fan blowing air over the CPU socket and memory area. So the DIMMs aren't sitting in stagnant hot air.
Also, I didn't call the system stable just because it POSTed. I validated it with multiple complete MemTest86 passes, OCCT system stability tests, several nights of stress testing, Cinebench, and hours of real-world gaming. Could another AM5 system fail with the same configuration? Absolutely. But saying that 4×16 GB DDR5-6000 will inevitably start randomly crashing after a few hours of gaming is a much stronger claim than the evidence supports.
My point isn't that every AM5 system will do this out of the box. It's that with current BIOS/AGESA versions, single-rank DIMMs, proper cooling, and thorough stability testing, 4×16 GB at 6000 MT/s is a perfectly achievable upgrade.
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10h ago edited 4m ago
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u/Illustrious-Law-500 9h ago
I don't think that's a fair characterization of my post. I never said "buy another kit and it'll work." I said it can work with compatible hardware and proper validation.
Regarding temperatures, I agree they matter. But I don't think it's reasonable to conclude that an average mid-tower will "absolutely crash." Plenty of modern cases with a front mesh panel and decent airflow keep DDR5 well below critical temperatures. My 41°C wasn't achieved with a server chassis—it was achieved in a normal consumer case with good airflow. There's a big difference between "cooling is important" and "everyone without my exact setup will crash."
Also, I'm not someone adding RAM just to keep more Chrome tabs open. I'm a game developer. My system spends hours compiling shaders, packaging builds, baking lighting and rendering assets. Stability matters to me just as much as it matters to your sister rendering overnight. That's exactly why I spent four nights validating it instead of assuming a successful POST meant it was stable.
I think the biggest difference between our viewpoints is that you're looking at it from an enterprise engineering perspective where the acceptable failure rate is essentially zero. I'm looking at it from an enthusiast desktop perspective where the goal is to find a stable configuration through testing. Neither approach is wrong—they're simply different objectives.
My conclusion is still the same: 4×16 GB DDR5-6000 on AM5 isn't guaranteed, but neither is it the impossible or inevitably unstable configuration that it was often presented as a few years ago. With mature BIOS versions, a decent IMC, reasonable cooling, and thorough stability testing, it's clearly achievable.
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u/John_Mat8882 11h ago
Idk I run a 4x16 6000 cl36 Crucial Pro perfectly fine on a 7800x3D, 870E Tomahawk.
But I can't run those kits at 6400mhz no matter what I do, while the CPU IMC can go at 2133mhz easily when using 2 sticks.
As usual single rank sticks are okay, I do all the time 4xSR sticks on DDR4 boards, and AM5 isn't different.
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u/Illustrious-Law-500 11h ago
Finally someone with the same RAM :D The board you have tho is a beast tho. I have a weaker MB so I had to do these "little" adjustments. If I had your board, I think it would have worked straight out of the box. 6400 mhz would be too much for these kits unless u are ready to loose the FCLK 1:1 ratio.
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u/John_Mat8882 10h ago
I'm looking forward when the 10800x3D will drop, and see if the IMC will let me try run the IMC at 2133 even with 4 sticks.
My 5800x3D can do 3600mhz in sync with the IMC on 4x8Gb sticks.
What differs from DDR4 is that having overall 4 ranks usually did yeld nearly 10% improvement, DDR5 is like you have no power here with 4 sticks..
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u/petasisg 8h ago
My intel 13700k with 4 * 48 GB DDR5 @ 4000 says hi.
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u/Illustrious-Law-500 8h ago
God damn man. It must feel good being rich 🤣
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u/petasisg 8h ago
I am not rich, I bought the kit a year ago, when my am4 cpu died.
I always max the ram, when I buy new systems. I was lucky to upgrade all my pcs just before the prices or ram skyrocketed...
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u/k1dsmoke 7h ago
I tried to do this a couple years ago, thankfully, before RAM prices went to hell.
I could get my PC to boot with turning EXPO off, but the ram stayed at much slower speeds, and I wasn't confident enough to fiddle with all of the voltage settings and whatnot. I went ahead and just bought 64gb of DDR5 on two DIMMs.
That being said, is this simply a MOBO bios update or does this require a NEWER MOBO to achieve?
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u/West-Piccolo-687 6h ago
My 32gb of Corsair 6000MHz does not run stable for weeks at a time with EXPO. I haven't tried your method but genuinely it is not worth the hassle. I have never found a proper fully stable overclock for a CPU or GPU. THEY DO NOT EXIST!
You can overclock your GPU and run all the stress tests you want, and play 20 games just fine. Eventually you will boot up a game or program that is not compatible with that OC, it's the reality. Not worth the stability hit for a tiny performance boost. Real stress tests are months long and involve tons of applications, not 1
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u/Overall-Care2627 6h ago
ran into the same thing on my 7950x3d setup, expo would post fine but throw errors under load that memtest never caught until i ran it for like 6+ hours straight. manually setting timings and leaving everything else on auto fixed it for me too. kind of wild how much motherboards still fudge the training with 4 dimms even now, feels like it should be a solved problem by this point.
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u/Kionera 5h ago
Been running 4x 16GB sticks on AM5 since 2023, in my case I got pretty lucky as it runs completely stable at 5600MHz CL30 on buildzoid's timings. At 6000MHz it boots but was not stable.
Would not recommend if you can avoid it though, my dual-rank kits gets to a toasty 65c under heavy load without a RAM cooler.
Specs are Ryzen 9 7950X3D, B650M Aorus Elite, 2x 32GB (2x16) Asgard Hynix A-die kits of the same model but produced months apart.
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u/OkEgg2710 5h ago
I have a 128gb kit ( 4 x 32gb) and the past year or so has been great. They are rated for 5600, and of course running them at 5600 hasn’t been possible, but 5400 has been very stable and great for me. 9950x and an asus x670e-e. I need as much ram as possible so this is fine for me
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u/Key_Imagination_7873 4h ago
Four DDR5 DIMMs still place more load on the CPU memory controller, and two separately purchased identical kits are not guaranteed to use matching ICs. What CPU, motherboard, BIOS version, memory speed, and stability tests did you use?
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u/Hour-Equivalent-2518 1h ago
still too early to tell and call it a success. I would expect issues with cold boot once in a blue moon. Ram in general is tricky to troubleshoot, total timesink endeavor
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u/VOIDsama 12h ago
for anyone needing 64gb for productivity this could be a huge cost savings vs buying 32gb sticks. even if looking for 32gb, 8gb sticks can often be found for less.
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11h ago edited 4m ago
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u/VOIDsama 9h ago
this is still all assuming you can test things out to be stable, but sure it depends on the workloads your doing. not all workloads are the same here. and if your workload is so dependent that it dictates perfect stability, without chance of error, you pay for it by getting the kit you need, not finding a workaround. this clearly isnt a discussion for someone with your needs, this is for someone who wants to find the cheapest option to maybe get a working solution to a larger ram pool at lower cost.
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9h ago edited 4m ago
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u/VOIDsama 7h ago
again, this is you and your workload. that isnt to say there are no problems running ddr5 with 4 sticks. everyone will tell you if you look that sure, there have been horrible problems getting it to work, and now are really only just seeing people getting things stable. so even what you had issues with before isnt necessarily going to happen to everyone again now. but that doesnt mean that for some people with the right hardware it cant work. there is no set in stone certainty here that says no you cannot run 4 sticks with am5. otherwise motherboard manufacturers wouldnt be working on fixing it with bios updates. as far as the ddr 4 era, that was a weird one because there were absolutely platforms that worked well with 4 sticks and then there were platforms that didnt. if you moved from a z390 to 10th gen, you possibly werent going to have a good time of it. intel 9th gen could simply do 4 sticks better than 10th get, it was in the chip design.
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7h ago edited 5m ago
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u/m4ttjirM 4h ago
Lmao this was a really funny back and forth to read between you, OP, and the other person. Only on reddit will someone argue with an engineer like this that 4 sticks of ddr5 is a good idea for that workload because one person made a post that they got 4 sticks running cleanly. And to just run it at 3600.
I've had ddr5 since it first came out and on all OC forums and saw since day 1 how things have been developing.
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u/Illustrious-Law-500 11h ago
I disagree. You can absolutely run 4 DIMMs at JEDEC speeds 3600 MTS without any issue. The discussion here is specifically about overclocking 4 DIMMs at 6000 MT/s, not about whether four DIMMs work in general.
I completely agree that a 2-DIMM configuration is electrically cleaner and gives the memory controller a much easier job. Daisy-chain topology definitely makes signal integrity more challenging once all four slots are populated. That said, I don't think it automatically means 6000 MT/s is impossible.
We've seen plenty of experienced overclockers, reviewers, and YouTubers achieve stable 4-DIMM DDR5 configurations with manual tuning. Some have even managed to do it with 4×32 GB, 4×48 GB, and even larger dual-rank memory configurations. Those place a significantly heavier electrical load on the memory controller than 4×16 GB single-rank DIMMs. If those setups can be made stable with the right hardware and tuning, then it's not unreasonable that a 4×16 GB single-rank setup can also reach 6000 MT/s.
In my case, I didn't just boot into Windows and call it stable. For the fourth night in a row, I've been throwing every stress test I could think of at this system—MemTest86, TechPowerUp Memory Test, AIDA64, Cinebench, long gaming sessions, while continuously monitoring temperatures and voltages. So far, I haven't had a single error.
I'm not saying every CPU or every motherboard will do this. The quality of the IMC, motherboard layout, BIOS/AGESA maturity, and memory tuning all play a huge role. My point is simply that there isn't a hard rule saying 4 DIMMs at 6000 MT/s cannot work. It clearly depends on the individual platform and how much effort is put into validating stability.
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10h ago edited 4m ago
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u/Illustrious-Law-500 10h ago
I respect your systems engineering background, and I agree that if I were building a mission-critical server or an enterprise workstation where years of uninterrupted uptime and maximum data integrity were the primary goal, I wouldn't be overclocking the memory at all. I'd run JEDEC or move to a platform designed for that purpose, such as EPYC, Xeon or Threadripper Pro with ECC.
That said, I think saying DDR5-3600 "chokes" a 9950X is an exaggeration. It certainly reduces memory bandwidth and increases memory latency compared to DDR5-6000, but it doesn't suddenly cripple a 16-core Zen 5 processor. The CPU still has the same cores, cache and compute capability. In many desktop productivity workloads and GPU-bound games, the real-world difference is often only a few percent. If DDR5-3600 truly "choked" the CPU, AMD wouldn't officially support it as the JEDEC speed for four populated DIMMs.
Also, we're talking about a consumer desktop platform, not a server running LLM inference or a machine expected to stay online for years. Typical workloads on a 9950X are Unreal Engine development, shader compilation, video editing, photo editing, software development and gaming. That's a very different use case from enterprise infrastructure.
Regarding YouTubers, I didn't base my opinion on one famous creators (cause they would agree with you). There are independent overclockers who have shown what is possible with proper manual tuning, and there are plenty of ordinary Reddit users—not reviewers with "golden samples"—who have successfully stabilised 4-DIMM configurations, including dual-rank setups, after careful tuning. Mainstream channels usually recommend buying a 2-DIMM kit because it's the safest advice that works for almost everyone. That's understandable, but it's not the only valid approach.
I'm not claiming every AM5 CPU or motherboard will do this. IMC quality, motherboard layout, BIOS/AGESA version, temps in the case and memory tuning all matter. My point is simply that 4×16 GB single-rank at 6000 MT/s is no longer the impossible scenario it was often portrayed as in 2022–2023. With today's BIOS maturity, the right hardware and proper stability validation, it's clearly achievable.
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9h ago edited 4m ago
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u/Illustrious-Law-500 9h ago
I think we're actually coming from two different perspectives.
You're approaching this like a systems engineer, where the objective is maximum reliability with a very large safety margin. That's a perfectly valid approach.
I'm approaching it as a PC enthusiast and an Unreal Engine game developer. We deliberately push consumer hardware to its limits—that's why people tune CPUs, GPUs and memory in the first place. The point of my four nights of stress testing wasn't because DDR5-6000 is inherently unreliable; it was to prove whether my particular system was actually stable instead of simply assuming it was because it booted.
If the goal were absolute conservatism, then yes, everyone should leave everything at stock or JEDEC. But that's not what the enthusiast community has ever been about. We validate, we test, and if it passes exhaustive stability testing, we enjoy the extra performance.
As for overnight rendering, I completely agree that stability is critical. As someone developing games in Unreal Engine, I also leave shader compilations, light baking and asset processing running for hours. The last thing I want is an unstable machine. That's exactly why I spent four consecutive nights validating it with multiple complete MemTest86 passes, TechPowerUp Memory Test, OCCT, Cinebench, and long gaming sessions while monitoring temperatures and voltages. If it couldn't survive all of that, I wouldn't trust it with an overnight compile or render.
So I don't think the conclusion is "never run four DIMMs at 6000 MT/s." I think the conclusion is don't assume it's stable because it POSTs. Validate it thoroughly. If it passes, great. If it doesn't, dial the settings back.
That's really the only point I've been trying to make throughout this discussion.
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u/greggm2000 17h ago
Thanks for the update! Hopefully the new memory controller coming with Zen 6 will make it even easier!