is it normal that I have 493 h/s on 7950 with 14.6 driver?..
No thats not normal

Thats too good to be true...
Nvidia performace is still crap compared to AMD

yes, I saw others results and I understood that my hashrate is to big, but...
http://i62.fastpic.ru/big/2014/0626/a8/c0fa6b05a14511952a161884b7fa48a8.pngI have only Asus 7950 (1150/1600) - I assure you guys
And as I can see in pool stats - that is real speed
1150/1600 - That's a cause. So nothing special...
Btw i got 458 h/s on 7950 (1000/1250).