I put this system together today and it never posts, not even beeps. The CPU loading LEDs on the motherboard has 4 lit. I used the 2nd and 4th slot for my RAM. It goes 5-15 seconds roughly and just reboots. I cleared the CMOS. Everything installed works fine in my other system (I am running on all of it now). I am hoping the seller didn't sell me dead setup. They had great feedback on eBay and everything came in original boxes/manuals/etc. I verified no pins were bent both when I got the motherboard and again once it failed. I want to swap in my slower PC-1600 memory next time to see if that works. I am also going to try the PC3-2133 in my GA-990FXA-UD3 once I find out if it's supported. Any ideas would be helpful, going to try this again next weekend.