Alright so my brother wants the best graphics card he can put into his Dell Optiplex GX620 Small Form Factor He wants me to get it from Microcenter, since the store is like 5 mins from our house and he could get it real quick and doesn't have to wait for it to be shipped. I know looking on Tigerdirect or Newegg would be the best solution/price but he's decided going to Microcenter.

The problem I notice is that the Dell Optiplex GX620 has a 275 watt PSU and I think the slot is PCIe 2.0, and I'm not 100% sure on what to get, since alot of cards these days require 300+ watts and some with an addition power connector. I was looking for that Radeon x600 that the Dell site showed, since it looked like the best it could support, but couldn't find it on Microcenter site.

Here is the link to the site to look through, and I told him not to expect great results since the pc has limits.

Thank you for any info