Question Why does my computer refuse to boot if I run my ram at advertised speeds? (xmp enabled)

Doomish

Reputable
Jul 23, 2016
13
0
4,510
Hello. I'm having a headscratcher of an issue and I think someone with more experience than me might be able to help me diagnose my problem. I have 48gb of Corsair Vengeance RAM (DDR4, 3200mhz, 16x2 + 8x2) in an ASRock X470 Taichi motherboard, and my computer just plain refuses to boot if I enable XMP. It turns on just fine- proceeds to BIOS, fans spin, mobo + RGB + peripheral lights come on, and the windows logo appears... but then it freezes after a split second of attempting to boot. After this, it stays stuck this way until I reset the UEFI to default and get in long enough to launch in safe mode and attempt startup repair/do chkdsk. The computer will not run if my DRAM Frequency is at anything higher than 2133mhz. For reference, the 16x2 RAM is Corsair Vengeance Pro RGB, and the 8x2 RAM is Corsair Vengeance LPX.

9jKzG34.png


It just won't go any higher than these exact numbers or else the whole thing just craps out. The RGB on the RAM does not light up when the problem is occurring, if that helps.

A short list of things I've tried:
  • Memtest to check if the sticks themselves are defective (they are not)
  • Checked if the slots on the motherboard are defective (they do not seem to be, any RAM works in them, just not with XMP enabled)
  • Updated motherboard firmware to latest (I heard Ryzen systems have a hard time getting RAM to run at advertised speeds on old BIOS, did not help)
What could be causing this?

edit:

Never mind, I was unaware that they have to be the same size/model for it to work properly. Taking the LPX (8x2) out and leaving just the Pro (16x2) worked fine. As I said, the Vengeance PRO is new and the LPX is old so I figured I could just mix and match, but it didn't like the combination.

cyTxxgX.png


It's working now!
 
Last edited:
48gb of Corsair Vengeance RAM (DDR4, 3200mhz, 16x2 + 8x2)

Such combinations of multiple kits of memory have no guarantee to be compatible together.

Workarounds to get extra memory to work include:
Lower memory clock speed
Relax DRAM timings
Increase DRAM voltage