extremely slow performance..card to blame?

[plutomaniac]

You will definitely see a huge improvement with that graphics card, most probably everything at maximum for Amnesia TDD. Your CPU is a beast performer (for it's time of course but should perform perfectly fine meaning no bottleneck at all), you have plenty of RAM and a solid operating system. If I were you I wouldn't worry at all. Once you get that graphics card you should be ready to game. Personally I would go for the Radeon HD 7770 which has the best value for money option (price/performance ratio) but you should still do ok with the 7750.

EDIT: 4 cores + 12MB L2 cache...damn, that CPU must have been an extreme edition or something back at 2008. Oh and yeah, that graphics card couldn't be any worse for such a system. It's embarrassing really...