The two main failures on this model are first the video card, then the power supply. The power supply is sneaky as it will partially fail. It usually begins with unexplained reboots. This may only happen once or twice a week. However as time goes by the frequency of the reboots increases until you just can't stand it anymore as it's doing it 5-9 times a day. On the 6 machines I've worked on, all responded well when the supply got replaced.