Hi, we think the problem whit the computer is the motherboard so we now need help to find a good motherboard for AM2+ (6400+). We did first look at XFX nForce 750a (MD-A72P-7509) but it says it only supports socket AM2+ CPU's up to 95W and the 6400+ is on 125w. Maybe ASUS M3N72-D, supports CPU up to 140W ? Thanks!