Solved! 4x16GB not on QVL for AMD X570 3900X, is that an issue?

[Johnmcl7]

I've been going in circles trying to work out compatibility and figured I'd just ask. I'm planning a new system with an AMD 3900x, Asus ROG Crosshair VIII Wifi and two sets of 2 x16GB Vengeance 16GB 3200Mhz memory to give 64GB total. Unfortunately while a single 2x16GB set of ram is shown on the QVL, if I'm reading it correctly it's not qualified for four sockets:

https://dlcdnets.asus.com/pub/ASUS/mb/SocketAM4/ROG_CROSSHAIR_VIII_FORMULA/ROG_Crosshair_VIII_Series_Memory_QVL_190801.pdf

The Corsair LPX 4x16GB 3200Mhz set is missing as well (CMK64GX4M4C3200C16) although I've seen plenty of builds that seem to use 4x16GB without issue. Also Crucial list 4x16GB kits as compatible that aren't on the Asus site, I've also noticed 4x16GB kits seem to be a lot more expensive than buying a pair of 2x16GB kits.

I'm not concerned about overclocking or maximising the performance but I don't want to risk stability, am I worrying about nothing?

 

[UsandThem]

You can use Crucial's tool to see what RAM will work with the motherboard: https://www.crucial.com/usa/en/advisor

Corsair has one as well, although they don't update it very often, so that motherboard might not even be listed: https://www.crucial.com/usa/en/advisor

Motherboard manufacturers really don't test many RAM kits, so I always check the RAM manufacturer's QVL instead.

 

[Raduque]

Only half my ram is on my motherboard's QVL. I have 2x Corsair CMR16GX4C3000C15 and 2x G.Skill F2-2400C15-8GVR.

The Corsair are on the list, the G.Skill are not, but all 4 sticks are working fine at 3ghz 16-17-17-35.

I'm running an R5 3600 on an MSI B350M Bazooka board.

 

[DrMrLordX]

I ignore QVLs unless I plan to gripe at someone about advertised XMP settings not working, which is something I never do. Hand-tuning is pretty easy now with stuff like Ryzen Memory Calculator.

The only thing you really need to know is: which ICs are in the DIMM? There's not much difference between DIMMs except that sometimes the really expensive ones have low-noise PCB designs. Most of what makes fast RAM fast is binning.

The RAM you're looking at is Samsung b-die in a dual-rank configuration. It'll behave pretty much like any b-die, though the memory controller will have to work a little harder to maintain high clocks with that many memory ranks. Ironically, the C8H might do a worse job with that RAM versus older x370/x470 boards that used T-topology instead of daisy chain.

 

[Johnmcl7]

You can use Crucial's tool to see what RAM will work with the motherboard: https://www.crucial.com/usa/en/advisor

Corsair has one as well, although they don't update it very often, so that motherboard might not even be listed: https://www.crucial.com/usa/en/advisor

Motherboard manufacturers really don't test many RAM kits, so I always check the RAM manufacturer's QVL instead.

Thanks for the reply and you're right Corsair haven't updated it for the motherboard I want to use.

I appreciate the prompt responses and have ordered the memory and the rest of the system, it can be tricky searching online as you're much more likely to find people with issues giving a misleading view.

 

[Johnmcl7]

I went ahead and bought the four sticks of Corsair LPX Vengeance 16GB 3200 ram which I've just finished building the PC with and it's working great, booted up straight away and seems fine with gaming.

Thanks again for the prompt assistance which is just what I needed to go ahead with the build.