I'm thinking yes and no. It will run 64 bit apps since thats the only os that can handle them, and i'm not truthfully sure about 32bit apps. I think that just having the 64 bit processor is a big improvement in my opinion. They have like super fast fsb's on them, like around a gig. Most other of the amd's have like 400 mhz fsb's on them. If you didnt already know, the bus of the processor [is used to determine] how fast the rest of the motherboard can talk with each other. I know this may sound like a processor talk, but the other thing that may change how fast your pc is the cache, but i'm pretty sure like all of the amd's have almost similar cache sizes. Correct me if i'm wrong. I, myself, will just be getting an athlon64 sometime soon, and just leave regular 32 bit windows. My friend has winxp64osbeta and he said it takes him super long to find a driver for his hardware, if its even available.