does the gpu have a heatsink or a fan on it? You may need a fan to o/c the card. Either one that is designed to for cards or what I did to my old GF2MX was to srew on a old 486 fan onto the heatsink and it seemed to work. I was able to o/c it from 166/150 to 200/220. Not sure how a mx400 would scale. Right now I'm running a GF4ti4400 at 4600 speeds. Haven't tried going much higher. What I found that really helps is to have a 120mm fan that is mounted ontop of the pci slots and blows down onto the card. Really helps keep air moving and things cool.
COLINMAN
"It takes a big man to admit he is wrong, I'm not a big man." Chevy Chase, Fletch Lives
"A fighter pilot is always on the offensive. If there is a MiG on his six, the MiG is in a very good defensive position, while the fighter pilot is in a very poor offensive position"
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