Recently the fan on my 600 W Cooler Master Power supply started to make increasingly loud noises. Upon investigation I found that the fan was locking up and then fighting to spin. I tried dusting down the system but had no luck in getting the fan to function properly. So yesterday I went out and purchased a new 650 W Antec Power Supply to replace it. I powered down my system, shut off the power supply, and removed the power cable. With an ESD strap tethered I documented the connections, removed the cables, and replaced the Cooler Master with the new Antec PSU. I then powered the box back up heard it post, figured it was fine and put my monitor back on it. This is where my problems begins. My system configuration is as follows: motherboard: nforce 6801 sli vid card: 8800 GTS RAM: 4 GB DDR2 HD: two 76GB raptors in a RAID 0 for my OS HD: two 500GB 7500k drives in a RAID 0 for storage PSU: 650 W Antec OS: Windows XP When I power the box up all fans are active, the hard drives spin up, the mother board posts normally, and displays the "FF" status on the motherboards LED indicator signaling a normal boot process. The BIOS runs and I see it detect my two RAID stripes and it indicates that they are healthy. It gets to the boot from CD check and goes to a blank screen. It does not progress any further. I am not of the opinion that the old PSU somehow damaged some system components as the actual power output was fine and my system functioned as expected, it was just the fan making nosies that spurred this replacement. I thought maybe removing the power caused the motherboard to lose its settings and changed the boot order to boot from my second stripe which is just for storage. Logging into the BIOS I confirmed this was not the case. At this point I am kind of at a loss, any suggestions would be greatly appreciated!