Strange issue running 4 sticks of ddr5

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Got a strange issue with a build
Motherboard: Tuff Gaming B650-E Wifi, Newest Bios, default settings-no oc
Ram: corsair Vengeance 4x16 gb kit
Cpu: Ryzen 7900x

On fresh bios or clr machine boots normally into windows runs stable, now the issue is when you shutdown or restart with 4 sticks the motherboard light is stuck on yellow.
Pull out one pair , clr bios machine runs normally i can shutdown/restart with no issues.
Ran memtest86 no errors found.
Trying to find out why it won’t run properly with 4 sticks?.

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do they work at 4x 3600 ?

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Because for the most part none of the DDR5 dual-channel platforms should have 4 slots.

The memory controllers basically have a stroke with 4 DIMMs; the official spec from AMD on a 7900X is a very familiar 3600MT/s the moment you install 4 sticks. Yes, that is a severe downclock.

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This is very true on 7000 series CPUs and boards - I can confirm 4 32GB sticks on my 7950x and Asus x670e Crosshair Extreme board downclocks to 3600. Early on you were lucky to get it stable even at that speed, though that seems to have improved with BIOS revisions. Anyway, most of the time if I’m not doing anything that needs 128GB, I run with 64GB/2 sticks just for the performance.

From reading various articles, It sounds like the 9000 series + x870 boards have beaten this and as much as 6000, maybe even more, on 4 sticks may be possible. Can anyone confirm?

If so, single best reason to upgrade to x870 mobos IMO.

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Yeah, using more than two dimms on consumer platform should be the last resort due to myriad of potential issue.

Try moving around single pair to dimms to replicate the issue. If it reappers in different slopts, then motherboard or cpu are the issue.

But this seems like the typical more dimms than controller can actually handle, QED.

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@HappySweeney’s close on 2DPC 2R 6200 and MSI supports 2DPC 1R at 6400. Not sure if @ubergarm’s looked at quads, I’ve currently only got a dual DIMM Granite Ridge config.

FWIW the 7950X B-die build I did last year had no problem with 4x48 at 4800. Didn’t like 5200 but I haven’t had a chance to check back with AGESA 1.2.0.2.

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Yeah, basically if you want 4 DIMMS either take the memory speed hit - or go to HEDT

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Particularly, if your sticks are dual rank, that puts an imense strain on the memory controller. You will always see a downclock to about 3600.

The rule of thumb with DDR5 (until CUDIMM becomes a thing) is Intel only supports 2 sticks. If you want to do 8000mt, then only use 2 sticks. If you want to do 4 sticks of 6000mt, use single rank dimms. If you want 4 sticks of dual rank, then tale the 3600mt speed. If you cannot get stable with the auto settings, you will have to manually set timings.

Peep this channel. He does all of the deep dives on memory and infinity fabric.

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