Best video card for my computer? Help!

Ok i have a Dell Dimension E510 with a 305 watt power supply

I have dual core processors and one gig of Ram i want to be able to be play some more recent games

If i cant run anything good please let me know how to upgrade my Computer for the least cost for the best gain performance wise.

I want to be able to run Fallout 3 on medium or better if possible any feedback will be helpful.

Thank you for any Help!

No its dual core i dont know why it just is and how much will a 550 power supply cost?

Google a program called CPU-Z. Download and run it. That will tell you exactly what kind of processor you have.

PC Power and Cooling sells Dell form factor PSUs, but as I said, if you have a Pentium 4, it would be a waste of time and money to upgrade.

http://www.pcpower.com/products/power_supplies/dell/

Ok i checked and i was right ok i think that we customized the Pc or something if you dont believe me just assume that i have Pentium D and not Pentium 4 i heard that dell PSUs were underrated i also heard that a ATI radeon HD 4670 would also work for my System i even heard that a 8800 Gt would run but lets not get off topic do you think the 4670 would run?XMoshi