Probably one of the AM2 socket Athlon 64 x2 CPUs, but you'll have to check with Gateway to make sure the board's BIOS (and power supply) supports the faster CPU. In any case, I think the 6000+ is the fastest out there, and that won't make a noticeable speed difference, so your best bet is to buy a new computer.
Thanks for the speedy response.
I was looking to see if I could get by that option, but it seems as though it is the only logical and practical way out. I'm maxed out on RAM so that was the only out.
School District of Palm Beach County