If you're going for the 1.2GHz Athlon, make sure that: a) you use a motherboard capable of DDR (e.g. Gigabyte GA7DXR); b) you get the 266MHz front side bus version of the Athlon as opposed to the 200MHz version and set the motherboard up to run at that speed (there's no price difference between the two versions); b) use branded PC2100 DDR SDRAM not PC1600 or (worse) PC133. If you do these 3 things the performance increase is quite noticeable.