Because you have an HP model, you need to verify that whatvere you get fits. The p/s unit itself is ATX12V class but it is physically different from typical generic p/s. You can check this website for truly hi-quality unit and one that can fit: http://www.pcpowerandcooling.com and yes they're expensive but worth it. Of course, google for any HP ready p/s units or check HP parts surfer website for a better replacement beyond 250W, I believe 320W can be found or better.
tada
-----Willy
I currently have a 250 watt power supply, and i want to upgrade it to a 400 watt so I can get a new graphics card. My question is, do I have to get a make and model specific power supply, or can I buy a generic one in the store and put it into my computer?
I have a hp pavilion a520n
3200+
512 mb pc2700 ddr sdram
160gb 7200RPM UDMA HD
DVD+RW/CD-RW
CD-ROM 48x

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