the GTS 450 is a good value if it's around 80-90 bucks, not for $130. For $130 you should be able to find a 768mb version of the GTX 460 or for a little less the HD 6770. As low as your resolution is though a GTS 450 would be a pretty good card, just don't spend $130 on it.
I would go for the 6770.Its quite a bit faster than the gts 450.But at that resolution you should be fine with either.If you plan on going higher resolution your cpu is going to be the bottleneck in this situation.And for a few extra bucks The gtx 550 ti and the 6790 are the cream of the crop!Just watch out cause some of the 6790's require 2-6pin pci connectors,But either way will work fine with a 500 watt psu!
agreed. i spent like a month trying to spend only 120 or less on a card. the gtx 460 was what i set as a standard of performance, but was too high in price. the 5770 seemed to out perform the GTS 450 by quite a bit, so thats what i went with.
i think i completely ignored anything with a 6xxx as i assumed it would be too much. after more research, the 6770, and 5770 are about 99.99% identical in every way.