You'll hear this probably 20 more times, with this thread:
Dont buy a prebuilt computer, build your own.
If you search around the forums, you can find people looking for a new computer, and got recommendations for parts. Look for those threads, and pick out parts, and either get a computer built with those parts, or build it yourself.
Intel E6750...........PSN: ELBATROP
XFX nForce 650i Ultra
Patriot PC2-6400 8GB (4x2GB)
36GB WD Raptor
Samsung SyncMaster 931c
Samsung SyncMaster 750s
Windows 7 Home Premium 64