Thats a pretty fast system for general usage. Yes you will lose all your files if you reinstall. Just back them up somewhere and load them back on afterward.

WindowsXP does fine with 512 ram, especially if you're not doing anything intensive.....I think the most benefit will come from a fresh Operating System install.

I didn't mean a "bigger" hard drive to gain speed...I meant a faster one. A typical hard drive of today is about 6x the size and 2x the speed of an older one. The bigger hard drives are indeed faster due to the much higher density and recording technology they have. Then there's the super fast drives, like the Western Digital Raptor and Velociraptor....they are super fast. (I have one. )

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