u just have to know the type of psu u have to buy as theres like different variations for motherboard power connector. once u know u just got to buy one that meets the specs. to remove old just disconnect everything that is connected to powersupply (moterboard, hard drive, optical drives, etc) and plug the new one in to all the connectors u removed.
not to sound too naive, but what is involved in installing one?
can i do it myself, or do i have to drop cash to have it done? i hope it's the former and not the latter.

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