It's a good mid-range videocard although it doesn't perform a lot better than the same card with 256Mb memory.
For around 100 euro's it's a good deal, you didn't waste your money.
Btw; Are you serious about those CPU temperatures? Those are way too high! You should invest some of the money you saved from buying that videocard into a better cooler, or else you won't be playing games for much longer :(
Good luck,
Marcus