Still need a memory upgrade, too.
If you're going the memory route, check out NewEgg.com. At the very least, to get a feel for what your friend will need. They have a pretty good
memory configuration tool that can help you figure out exactly what kind of RAM his PC was designed to use.
They are my go-to online retailer for computer hardware. Especially for RAM and hard drives. Their selection is incredible, their prices are among the lowest, and their shipping is usually speedy (pay the $1.99 for expedited shipping). At least, in my experiences.
Good luck!
