Ok this is driving me nuts.
I cannot change the speed of my memory without running it at +0.5v.
My motherboard automatically resets itself on post no matter what setting I use (667, 800, or even 1066). If I leave SPD at auto and let the motherboard run it at 1066 on its own, it works fine with default voltage (which, as far as I know, is only 1.8v).
What the hell is going on here? I just set it to +0.3 (which should be 2.1v... the recommended setting for this ram) and I had to clear my CMOS manually to get the thing to post.
It doesn't make any sense. It runs perfectly fine at stock settings, but as soon as I change anything (faster or slower) it all goes to hell.
Is there some setting I'm missing here? Does anyone else have a gigabyte P35 board?
EDIT: Hmm... I think I may have found a way around this quirk.
When you change the ram SPD (the ram multiplier) the system does an auto reboot (sort of a double reboot I guess) to save and test the settings. When you adjust voltages, it doesn't. For some reason, the only time it successfully saves and applies the SPD settings (anything but auto), is when I have the dimm voltage set to +0.5.
So... I set it to +0.5 and set all of my overclocks. Saved the settings. It did its reboots and it posted just fine. But then I went back into the BIOS and set the vdimm back to +0.3. Saved settings. It didn't have to do the double reboot this time so the settings took and its still working fine.
I'm guessing the excessive voltage was what was causing my RAM problems after extended use. It was probably overheating. At 2.1 it should
I'll do some testing but I think I may have solved it.
I don't know why the RAM SPD change requires +0.5v the first time... and I don't really care as long as I can get this thing to work the way I want. Its probably just a gigabyte BIOS bug.