if you look on the side of the power supply it should show you specs of the power supply . it should show 5v 3.3v 12v and others . under or next to each it should show how many amps the "rail" is the 12v should be more than 15a . if it isn't then that might be your problem . here is a pic so you can see what i am talking about . see how it says 25a under 12v . thats what i am talking about . if your system is under 15a then it is working really hard if you have a p4 and a dvd going at the same time they both run on 12v . now i do agree that you need a good power supply in a system , but i don't think you have to get a "big name brand " to get a good power supply . the one that is in this picture is a supply that cost me 23$ shipped . and it is in an overclocked xp2500 system and hasn't burped on me yet