i try on win 7 64 and win xp
ccminer download from https://github.com/tsiv/ccminer-cryptonight
i replaced my geforce 660gtx which worked well

[2015-02-24 23:27:08] Ignoring algo switch, this program does only cryptonight n
ow.
[2015-02-24 23:27:08] Using JSON-RPC 2.0
[2015-02-24 23:27:08] 1 miner threads started, using 'cryptonight' algorithm.
[2015-02-24 23:27:08] GPU #0: GeForce 8800 GT (14 SMX), using 40 blocks of 8 thr
eads
[2015-02-24 23:27:08] Starting Stratum on stratum+tcp://qcn.pool.minergate.com:4
5550
[2015-02-24 23:27:08] GPU #0: Warning: block count 40 is not a multiple of SMX c
ount 14.
[2015-02-24 23:27:08] GPU #0: FATAL: failed to allocate device memory for long s
tate

http://shot.qip.ru/00CcJy-6jjb2KxP7/