Ummm 1st off it wasn't a 300W PSU it was a 400W, 2nd it only costs 30-40$ more then a 955 over here, 3rd a 955 or any other CPU cant be unlocked to a X6, it was not an upgrade, it was a complete build and is going to be used for CPU intensive programs more then anything else hence why i got the X6, and is cheaper then an i7 940 at the same performance. I went with the Corsair PSU as they are very good PSU's and is rated at the highest Volts on a single 12v rail. This system doesnt need anything more as the only intensive power hungry part of this build was the CPU and it wont even draw half of what the PSU can give out.