Today I made another upgrade. Instead of 1 GTX 280 I use 295, so it makes 3 x GTX 295 system with total arithmetic processing power 5,3 TGLOPS (single precision).
Theoretically my upgraded system is capable of 44 000 PPD F@H.
This is last upgrade of this rig. Next rig will improve performance just another 33%. Until now my test has been un-believable successful.