Hello, I'm planning on buying a new desktop PC, and here's the hardware list I assembled:
AMD Athlon 64 X2 4400+, socket AM2, 1024Kb c., 2.3GHz
HDD WD 160GB, SATAII, 7200rpm, 3.0 GB/s, 16MBc, SWD1600YS
DDR2 2048Mb (2x1024) PC6400 SuperTalent, T800UX2GC5, 800MHz
MB GIGABYTE M57SLI-S4 Socket AM2 NVIDIA nForce 570-SLI 6
SAPPHIRE X1800GTO, 256MB GDD3, DVI, PCI-ex
Please tell me if I put some incompatible components in this, or particularly if I could change something that would make it cheaper but not much less efficient

Thank you!