Possible issues with memory voltage? Need an opinion.

I'm having issues with a home build, I think i've narrowed the problem down to memory voltage, but just wanted to sanity check what I'm thinking.

I've got an Intel Quad Core @ 2666, an Asus P5K64 WS Mobo, and OCZ Reaper DDR3 RAM @ 1333. I'm seeing general instability in my system in both XP and Vista 64.

When I look at the specs page for my memory it says it requires a voltage of 1.75, but when I run CPU-Z it lists the voltage on each RAM chip @ 1.5 V. I checked my BIOS for a place to set the voltage on the RAM, but I didn't find anywhere to do it. So one question: Is this a likely source of the problem, or am I barking up the wrong tree?

FWIW running AISuite my CPU temp stays around 65 C under load, which I believe is okay....

First off, I wonder if your BIOS needs a flash to support the newer CPU.

I'm not familiar with that BIOS, but if there is no direct DRAM voltage modifier, look for a setting that adds voltage to the base 1.5V.

Also, what settings does the SPD tab give in CPU-Z?

Use Real Temp to measure your core temps accurately. Those do sound very high.... again could be over voltage caused by older BIOS. Did you clean off the surface of the CPU with a lint free cloth (Coffee filters work well) before installing the new cooler?

Push pins are notoriously subject to failure on coolers. Inspect them very closely to be sure all four are completely seated right.

This is why we push the Xigmatek along with the retention bracket. Bolt that sucker down and you'll get solid even readings.

You say you applied a "layer." Hopefully not too much. You only need an amount similar to a grain of rice... much more than that will drive those temps up.