Question Problem with XMP and RAM speed ?

[xBON3Sx]

Motherboard: Gigabyte X870E Aorus Pro Ice
RAM: 124GB Corsair Vengeance 6400 DDR5

Whenever I go into the BIOS and enable XMP to get the 6400 mt/s, I get a black screen and error code 15. Then I have to reset the PC for an hour or longer until it lets me in to the BIOS again.
PC will run fine with RAM at 4800 but anything higher and this is the issue.

 

[Misgar]

You've got several things working against you.

1). 4 sticks of RAM
2). AMD CPU
3). Vengeance RAM

Many systems (AMD & Intel) require lower memory clock speeds to remain stable if 4 DIMMs are fitted instead of 2. You can often overclock 2 DIMMs significantly faster than 4 DIMMs.

AMD CPUs tend to run at lower XMP overclocks than Intel CPUs. 6400MT/s might work on AMD with 2 DIMMs, but I'm not surprised you can't achieve 6400MT/s with 4 DIMMs.

Some people dislike Corsair Vengeance RAM for a number of reasons (try a search on Tom's).

Be thankful you can run 128GB Vengeance at 4800MT/s. Some mobo/CPU combinations have to be clocked slower than 4800MT/s with 4 sticks, e.g. 4200 or 3800MT/s are sometimes recommended.

If you bought two pairs of DIMMs, instead of a single kit containing 4 matched DIMMs, the two pairs will probably not be from the same batch or bin. The resulting small differences between each pair can reduce stability at higher speeds. Even if both pairs have exactly the same part number, this does not mean they're precisely matched.

I'm running a 7950X with 2 Kingston 32GB DDR5 DIMMs (64GB) at stock 4800MT/s.

I have 4 Vengeance 16GB DDR4 DIMMs (64GB) set to 3000MT/s on a 3800X.

Some apps don't benefit much from XMP overclocks, especially on AMD systems.

https://www.pugetsystems.com/labs/a...023-update/#Video_Editing_and_Motion_Graphics

 

[xBON3Sx]

See the weird things is i bought the aorus x870e pro ice and passed my other gigabyte mobo to my gf which is also ddr5 same ram sticks just black also from two different batches and hers run at 6000mts....but I have a newer mother board that won't. What gets me if I plug two from the same batch and only run two and try to turn on xmp I get an error code 15 and a dram light and have to spend hours restarting my pc until it finally let's me in bios. Bios is up to date as well.

 

[xBON3Sx]

It was also running on 4800 perfectly fine and just now switched to 3600....on its own even though in bios it's default is 4800. I've gotten it to clock all four at 6400mts but then it wouldn't let me load windows. I would fet a failed ramdisk.sys blue screen.