I learned something about RAM tonight. I put in the full 8GB of RAM into my [P5N-E] and the bios wouldn’t boot up. I read some helpful forum posts that directed me to adjust my RAM speed and voltage. Now the RAM I put in is 5-4-4-12-2 Mushkin (4 X 2G). Recommended voltage is 1.8-2.1V. This is 800MHz ram, but it needs higher voltage to run all 4 sticks. To be safe you can still run under less than 2.1V if you adjust the RAM timing to 667 MHz. I did that and it works like a charm. I’m now running Vista 64-bit with 8GB of RAM.