You have an interesting situation. Your motherboard is near its limit in terms of cpu(The best being an XP 3200+, which is not much faster than the 2800). So if you wanted a good performance boost, you would also need a new motherboard. However, most new motherboards also use ddr2 and pci express. Your best bet would be to save up for a bit and then buy an Athlon 64 X2 3600+ or X2 3800+, a new motherboard, some ddr2 memory, and a new video card. Depending on if you play games or not, you could buy a motherboard with integrated video, which would save you some money.