cant you just count the pins your self?? or look over at hp to see the specs. of there board to see ??
dude I will help you now .... your way better off ditching that hp motherboard and replacing it with a aftermarket one [like the ones we buy from newegg for our custom builds] cause if your replacing the psu so you can upgrade something like the vid card you may want to look over these forums to see that it may not take any card upgrade .. theres a lot of folks that go and invest in a nice high end card for there ''store bought '' computers just to find it will not work so ....good luck