But now I am getting alot of screen flickering. I changed my refresh rate on my Dell 1908WFP but it doesn't seem to help. I am thinking it may be the power supply. (If yall have any other ideas just let me know)
But my question is what kind of power supply can I get that can run this new gpu that will also fit into my case. Only thing I have changed in the case is the gpu.
Your PC seems to have a standard microATX case, so it's likely an ATX form factor power supply. Check whether the dimensions of your PSU (as seen from the rear of your PC) are 150x86mm (about 5.9 by 3.4 inches) to be sure.
However, omgitzfatal may be right that it's not necessarily your PSU. Yes, your new graphics card may bring your system dangerously close to max loadings, but check out all other possibilities first.