Ok, so I was applying a new coat of thermal paste (Arctic Silver 5), didn't get any on the board just on the CPU and GPU, a very thin layer so it wouldn't flow over onto the board, then i put a small piece of plastic just under the xClamp plastic to make the xClamps tighter, put everything back together, and it won't turn on at all. I was trying to fix my buddies red ring, and I got it working a bit when i took some of the old thermal paste that was on the board and put it onto the chips, but it RRoD shortly after. So I went to pick up some thermal compound today and I cleaned the chips, and the heatsinks, applied the Arctic Silver 5 as stated, and bam... It won't even turn on. Is there something I could of done wrong? It's not the power supplies because I tried 2 and they both work on the other xbox's I have. Please if anybody can help i'd greatly appreciate it.

crap wrong section of the forums.. I'm sorry guys.

What color, if any, appears on the psu light.

And if it's in the wrong section why did you post it anyways? I'm a little because it doesn't seem like you edited your post to say that, or else it would say "last edited by blah blah blah"

Weird.

I will move this for you.

Have you looked at all the USB ports? I have found that if one is broken and the metal is contacting the case it won't boot.

I straighten out the pins and make sure it boots. Then I take a glue gun and glue the port closed. That way you don't have problems in the future.