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gjsmo · ‎08-24-2014

I recently bought a Maximus VII Formula along with an i7-4790k to upgrade my aging AM3-based system. I kept my Kingston RAM on the basis that it's good enough for me (2x Kingston KHX18C9T2K2/8X 8GB kits).

Initially everything worked perfectly, including my RAM at its advertised speed of 1866MHz. Within a few days my CPU died however, which I RMAed to great success - Intel has truly amazing customer service. Upon receiving a new CPU, I find that my RAM no longer operates at 1866MHz, but works fine at the default 1333MHz. When trying to raise the speed to anything above 1333MHz, including using XMP profiles, the system refuses to boot, giving Q-code of 55 (Memory not installed). Additionally, attempting to use CPU Level Up feature results in the same Q-code, which also did not happen before the CPU RMA.

What could cause this? I have checked the CPU socket for bent pins, and all of them appear pristine. I've tried individual DIMMs (no change), remounted the CPU and cooler (no change), and tried resetting the UEFI (no change). I know that the RAM isn't on the QVL, but just the same it worked before the CPU RMA. I have the exact same model of CPU as before, so I can't think of anything that would've changed.

I should note that the system works perfectly at stock clocks. Rock-solid for gaming, CAD work, Linpack etc.

Chino · ‎08-24-2014

Set up your memory manually. When using 2 separate kits, XMP might not always work. If you need help with the manual method, there is a guide linked in my signature.

gjsmo · ‎08-24-2014

This results in the same issue.

Chino · ‎08-24-2014

Remove one of the kits. With the other kit installed, try XMP and manual settings again. Did it work?

gjsmo · ‎08-25-2014

No change with just one kit or the other kit installed. I also tried an extra older kit (known to run at 1600MHz), no dice - this one was a boot loop.
I did remount the CPU and put on a bit more thermal paste, noting that the heatspreader wasn't quite fully covered. Also no change.
On a hunch I cleaned both the socket pins and the contacts on the CPU. Still no change.

Chino · ‎08-25-2014

Remove all your sticks except for one. Clear your CMOS and upgrade your BIOS to the latest version using the EZ Flash utility in the BIOS. Right after it finishes, clear your CMOS again.

Enable XMP and see if it works with just one stick. If not, go the manual method again. And just out of pure curiosity, please post the exact values that you're using during the manual setup.

Costas · ‎08-25-2014

Since the only thing you have changed is the CPU and everything worked OK previously - It may point to an issue with the new CPU. Remember that the IMC [internal memory controller] is embedded within the cpu and this may be the culprit.

Do you have or know someone with a similar cpu that you can quickly swap and try it with?

ROG Formula VIII - Déjà vu Watercooled

Pahani · ‎08-26-2014

Costas wrote:
Remember that the IMC [internal memory controller] is embedded within the cpu and this may be the culprit.

This.

I don't have personal experience yet, but I've seen it mentioned that the IMC is almost like a second Silicon Lottery >.< I sure hope my 4790K is a good one, it's well past the return period due to waiting on parts to finish my build. And when I say parts, I mean M7F.

gjsmo · ‎08-27-2014

Chino wrote:
Remove all your sticks except for one. Clear your CMOS and upgrade your BIOS to the latest version using the EZ Flash utility in the BIOS. Right after it finishes, clear your CMOS again.

Enable XMP and see if it works with just one stick. If not, go the manual method again. And just out of pure curiosity, please post the exact values that you're using during the manual setup.

No change whatsoever unfortunately. Timings are 9-11-9-9 at 1.65V and 1866MHz

Costas wrote:
Since the only thing you have changed is the CPU and everything worked OK previously - It may point to an issue with the new CPU. Remember that the IMC [internal memory controller] is embedded within the cpu and this may be the culprit.

Do you have or know someone with a similar cpu that you can quickly swap and try it with?

I don't know anyone with an LGA1150 CPU whatsoever. I suppose I could try Craigslist or something, but I suspect they'd want me to buy it or the whole computer.

Chino · ‎08-27-2014

gjsmo wrote:
No change whatsoever unfortunately. Timings are 9-11-9-9 at 1.65V and 1866MHz.

Please go to the Tools section in your BIOS and enter the ASUS SPD Information utility to look at the timings for your RAM. The Kingston site didn't specify the tRAS for your kit. But I'm pretty sure it isn't 9.

If you're unsure about what to look for, take a screenshot with F12 with an USB pendrive present and upload the image here.

ASUS Maximus VII Formula won't POST past default clocks