Upgrading my mom's old system with spare parts I have laying around.(memory and such.) It's an Compaq sr1010nx with celeron northwood 478 processor. I have a spare P4 processor part number SL6PP 2.6ghz. Would there be much to gain by swapping out the processor?
The 3.06 533 fsb p4 is the fastest you can use. Starmicro has one for $27.50. You can find the link on pricewatch under cpu>p4 3.06. Be sure to get the desktop version; they also sell a mobile version, which may not work with your board or heatsink. You will notice maybe a 20% performance gain, especially with 1-2 gb of memory.