The combo Muffin posted is good. Here's a cheaper one:
Newegg.com - Computer Parts, PC Components, Laptop Computers, Digital Cameras and more!
I don't care for ECS boards, but that seems to be good.
Pair that up with this GFX card:
Newegg.com - XFX HD-487A-ZWFC Radeon HD 4870 1GB 256-bit GDDR5 PCI Express 2.0 x16 HDCP Ready CrossFire Supported Video Card - Desktop Graphics / Video Cards
You should be good to go.
Newegg.com - Computer Parts, PC Components, Laptop Computers, Digital Cameras and more!
I don't care for ECS boards, but that seems to be good.
Pair that up with this GFX card:
Newegg.com - XFX HD-487A-ZWFC Radeon HD 4870 1GB 256-bit GDDR5 PCI Express 2.0 x16 HDCP Ready CrossFire Supported Video Card - Desktop Graphics / Video Cards
You should be good to go.