Problems with new Video card

[intent]

Greetings All,

I installed a Nvidea 7600 into one of my machines (well both of them actually) but in one of them I am getting Random Blue Screens of Death with the Error

IRQL Not Less or Equal

I have tried downloading newest drivers (and ran drivercleaner pro before new drivers and before new card to make sure I got rid of all the other drivers)

I have all the settings on default

I have a 364 power supply and the card I bought only requires a 300.

My system stats are

Windows XP Media Center Edition 2005
2.8 Gighz Intel Dual Core Processor
250 Gig Hard drive
1 gig of ram

There is no rhyme or reason to when it is going to shut down
Sometimes I can play for hours and no shutdown
Then sometimes it just poofs after 5 minutes of browsing the net
I ran Memtest for 2 hours and there was no errors
I have run a test on the hard drive that came back clean
I am running out of Ideas
I updated the mother board drivers and checked to see if there was any new bios

It seems that the BSODs are getting less frequent but I just want to make them go away totally

Thanks in advance for any input

intent

[blue60007]

What *brand* power supply is that?

What video card was in there before?