Looking for suggestions. All constructive feedback appreciated.
My current environment is a Dell Optiplex 755 with 2.4Ghz dual CPU and ATI (28xx, older than old). I do not have heavy requirements for gaming, but would like to throw between $50 and $80 disposable income this month into adding a new graphics card, primarily or totally for the purpose of enhancing my SETI participation.

I have started reading the CUDA FAQ and am currently leaning towards a Nvidia GeForce 630 on the assumption that although the compute power is listed as identical between the 610, 620, and 630, the extra cores in the 630 will be a benefit (assuming that SETI can use the cores effectively).

Looking for feedback on the value of doing this to help the project as well as confirmation or alternative suggestions on appropriate GPU selection.

Thanks in advance