I need a graphics card for my hp pavilion p6000 p6597c

[rockieivory]

im trying to play diablo3

 

[2fast4thetown_down]

What are the specs of the hp pavilion

 

[clutchc]

Since you only have a 250W PSU, you need a card that receives all its power from the PCIe slot itself (75W). I wouldn't go any greater than these HD 6570s.
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=100007709%20600100181%20600083901%20600144218&IsNodeId=1&name=Radeon%20HD%206570

They should give you good frame rates up to 1440x900 (and possibly 1680x1050 with reduced settings). Diablo 3 isn't that demanding.