Pentium II @ 266MHz! ..overclocked of course, I'm not incompetent.
...OK, a real answer:
I'd ABSOLUTELY go with the AMD FX-4100, as it can (I have) go safely and comfortably to 4.2GHz per core. In-fact, buddy ol' chum, I would insist on AMD, just for this fact alone: It's more bang for your buck, since I purchased mine for £80.
Good luck.
EDIT:
With the remaining funds, grab yourself a decent after-market heatsink, if you haven't done so already, as it will ensure that CPU is kept nice and cool. I don't have an overly expensive heatsink (although it's pretty damn decent for such a TDP processor) and mine, overclocked on all 4 cores at 4.2GHz, maxes at about 55c when on decent moderns games, otherwise it stays at anything between 20c-35c, or if I mess around with some settings, and default clock it, it'll often be 6c-15c and that's not exaggeration, with 40c-48c being the max.