Question PC Won't Boot with RAM at Default Voltage


Senior member
Sep 24, 2000
I have an 5600X/X370 system with 2x16GB Crucial PC-3200 CL16 1.35V RAM, and after it has not powered on for a few weeks it won't boot. After a ton of troubleshooting I found that if the CMOS is cleared (the CMOS battery voltage was low and replaced) and the RAM resets to 1.2V at PC-2400, the system won't boot. The workaround that worked was to put in a stick of 1.2V JEDEC RAM (with no XMP), which will boot, change the RAM voltage to 1.35V in the BIOS, shutdown, and swap back to the PC-3200 1.35V sticks, which will boot at PC-2400, and then enable XMP.

The RAM sticks pass memtest once XMP is enabled at 1.35V.

Would the RAM going bad cause something like this? And if so will Crucial accept a RMA when it passes memtest at XMP settings but won't boot at JEDEC settings?


No Lifer
Aug 25, 2001
I think that the RAM doesn't even have to be "bad", per se, just "badly binned", such that it needs the XMP OCed voltage to run stable. As you found out, one workaround is to boot with a 1.2V JEDEC stick, set memory voltage in CMOS, save and exit, power off and install your higher voltage RAM kit, power on and go to BIOS, set Xmp, save and exit.

The other alternative is to, yes, replace the RAM kit.

But if this issue occurs often, even if the CMOS battery was replaced recently, then the mobo may be dying.
Dec 10, 2005
The RAM kit should run without issue if XMP is off, since it will run at the JEDEC spec. If it can't do that, I'd think you would want to contact Corsair and get a replacement.
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Apr 6, 2002
There's nothing wrong with running your mem at XMP. However, it should be stable at JEDEC. You should be able to run the ram at JEDEC. I've RMA'd ram that couldn't run at XMP. You're computer should be more stable when run at JEDEC. Not being able to do so, I would RMA the ram.
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