Phenom II 945
4GB of a descend brand of ram (OCZ, Mushkin etc) DDR3
AM3 motherboard asus or gigabyte
single radeon 4890 or dual radeon 5770s if you have the money
Antec three hundred case
Hang on, you mentioned you don't need a motherboard. In order to make recommendations, we need to know what socket so we know what CPUs are compatible.