PSU's to supply a 7600gt in a sff computer

[Mr_PieChee]

my brothers recently got a 7600gt for his computer, but he's been having some problems with it when it comes under a heavy load. the system keeps locking up and doesn't let anything happen (i.e. no task manager, no switching windows, not mouse or keyboard actions etc). we think the most likely problem is the power supply. he has a 220w psu, but a min of 300w is recommend for that model card. the only problem is finding a 300 watt psu for a sff computer is almost impossible. my question is could i attack an atx psu to the outside of the computer?

I don't know much about choosing power supplies, so I'm not really sure what I'm looking for. is there anything else i need to match up other than the watts and size?

 

[jshiffer]

hi you could probably find something here
http://www.newegg.com/
hope you can find wat you need

 

[jshiffer]

or you can try this
http://www.xoxide.com/arrow-matx-300w-psu.html