your gpu needs to be upgraded. it is a video card and wont play games other than the very basic 1s. its missing a lot of the extra features that gaming grade cards have lots more shaders being 1 of them to play games on nvidia hardware you need a minimum of about 48 shader units (9600gt is a good entry level gpu but is still pretty weak especially if you want to play bf3 which it wont). yours has 16 which means you can play games from 2000-2005 quite well in some cases but anything made after that you will struggle with.
id recommend a gts250 as a bare minimum and for medium a 560ti i wouldnt recommend anything higher for risk of bottlenecks but with an oc i have seen the q8300 handle a gtx 570 without issues.
so yeah get a new gpu and a power supply to power it if you only have a 400w or less. 450w for a basic gts 250 a 650w for a 560ti will be pretty sweet