Can these parts work with my set up?

[Leuce]

Gtx 750, and 500b 500watt evga atx in hp pacillion p7-1187c

 

[Kekoh]

That PSU is more than enough. You are good to go!

 

[zeph_yr]

Yep, they should both work. If you are only running a GTX 750, it should be able to run on the computer's stock power supply. Maybe buy the GTX 750 first, and if it runs 100% on the current power supply, then you don't have to buy the new power supply.

 

[Kekoh]

The GTX 750 requires 20A on the 12V rail, which his stock PSU does not have. I think it only has 8A. He will need to get a new PSU, and the one he chose will even be able to run a future upgrade if he buys a more powerful card (EVGA 550b has 40A)

 

[zeph_yr]

In my experience most HP power supplies have 18 amps on the 12+, which is 2 amps short but still enough to run it reliably. But it's best to play it safe I guess.

 

[Kekoh]

Well, I looked up the specs for the p7-1187c and the only information I could find was showing that it maxed out at 8A. On this page: http://h10025.www1.hp.com/ewfrf/wc/document?docname=c03017283&cc=us&dlc=en&lc=en#N1252