My opinion, listed by performance in each row. Most common (non oem) cards.
GTX690, GTX680, GTX670, GTX660Ti, GTX660, GTX650Ti Boost, GTX650Ti, GTX650, GT640 (Kepler).
Geforce GTX 590, 580, 570, 480, 560 Ti (448), 470, 465, 560Ti, 460, 550Ti
Tesla* C2050/C2070 (Workstation), M2050/M2070, S2050 (Data Center)
Quadro Desktop* Quadro 6000, 5000, 4000, 2000, 2000D
Should Work but are inefficient:
Geforce GTX 295, 280, 275, 260-216 (55nm), Tesla10, Tesla20, 460SE, GTS450, Quadro 600, 480M (CC2.0)*, Quadro Mobile* 5010M, 5000, 4000, 3000, 2000
Note on the GT240. This card no longer works; CC1.1 and CC1.2 cards (such as the GT240) are no longer supported.
The GT240 was a good card for the earlier 6.05 and 6.12 apps. These were replaced with the 6.13 app and then the 6.14 and 6.15 apps because Fermi cards would not work on the earlier apps. Apps tend to be upgraded to introduce support for new cards and improve performance for high end cards. The project can only support 2 apps.
*The Tesla and Quadro cards are very expensive compared to the GeForce cards, so these are only really applicable to business users.
Any mobile cards are recommended rather than highly recommended because they could cause heat issues with the notebook - it's up to you to determine if you want to use them or not. Only CC2.0 cards are Highly Recommended.
The Highly Recommended cards are most suitable for the long tasks. Other cards will also run them, but you should reconsider your system usage and Boinc cache settings.
Non-recommended cards should not be used with long tasks.
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