So I built a new desktop around November of last year. The motherboard is an Asus Z170-A and the processor is an i7-6700K. Originally I got a 16GB memory kit, with two 8GB modules. Recently I wanted to double my memory to 32GB, so I bought an identical kit of memory. Both memory kits are this: CMK16GX4M2A2666C16 and here is a link to the specs.
My problem is that the computer boot loops when I enable XMP. The system seems to run fine when XMP is disabled.
I have been looking into this, and have figured out that even though the kits have the same model number they still may have slight variances that make them not work together. Is this true? If so, is it worth my time for me to go through the timings of each kit in the UEFI to see if there are differences? When both kits are installed all the timings are identical. I have even tried bumping the memory voltage just a smidge, but that didn't help.
What can I do? I want to overclock with this system, and I wanted the memory to be running at 2666. And I really do need 32GB of RAM.
simple answer is dont use XMP. long answer is dont use XMP and set ram timings to XMP settings by hand. bump voltage up two to four settings. or you can relax the CAS latency a bit and up the speed. to get close to XMP settings. if it was me i would not use XMP at all and just OC the shit out of my CPU and not care about the ram speed.
but i am an AMD guy that has the advantage of multiplier OC and FSB OC. and having separate ram multiplier settings. i have not OC'd any intel systems since the I7 920 so i am way out of date on intel.
Yeah, this is probably my first Intel system since the Pentium 4 days, so this is all new to me as well.
I just tried setting the memory speed to 2600 (instead of 2666) and leaving XMP enabled. To my surprise the system booted just fine. I am currently running the stress test in AIDA64.
edit: On a side note, what is the best way to stress test? I heard that using prime95 is not good on Intel systems.
Are you sure that the model number of the kit is exactly the same? To be honest I'm not surprise to see a Corsair LPX kit failing on an Asus board. As looming-hawk said just punch in manually the XMP values and see how it goes.
Populating all slots puts a little extra stress on the memory controller, so it's possible that it was nudged just over the edge on the speed with four sticks. Even if it shouldn't happen, at least the difference is negligible. A newer BIOS might help with such things, but if it works now then it's not worth the bother for this alone.
Yeah, so far it's quite stable at 2600MHz instead of 2666MHz. Dunno. I've always heard that populating all the DIMM slots puts a bit of strain on the controller, so maybe that's it. Since everything past 2133MHz is technically overclocked it might just be that.
Now I have the issue of my Corsair H100i GTX shitting the bed. Intermittently. Can't catch a break.
These kits are spec'ed for 1.2v. If what you are saying is you ran XMP with two modules, added two more and then had problems, the answer is simple. You just need to bump the memory voltage. Try 1.250-1.300, up to 1.35v. Guarantee this is your problem.