Yes, I have an AM3+ motherboard, and my graphics card is an XFX Radeon HD
5770. Any ideas as to how limited this would make my gaming experience?

All I'm saying is look beyond the cpu to improve your gaming experience.
For me, buying a big cheap 28" 1900x1200 lcd monitor for $220 a couple years
ago gave more enjoyment than any other upgrade I've ever installed, but
running games at native resolution meant a new videocard, in my case a gtx
465 bios-modded to a 470. Great card, but showing it's age for the newest
games like BF3/Skyrim/Metro2033, which would have to be run at lower
resolutions, etc.

There's no requirement to even buy new! Newegg.com has a refurbished
GTX 560 with 1yr warranty for $160, or a GTX 560Ti for $220, & both Newegg &
Tigerdirect have 27-28" monitors in the $250 range. A 560Ti is roughly
equal to 2 radeon 5770 in crossfire. So $500 would give you a dramatic,
immediately obvious improvement in your gaming experience.

rms