I was searching on Gigabyte web and found latest bios, which was same as my actual one, so yes i have actualized bios . When i was checking MB´s Cpu compatibility list, E5700 wasn´t even there, that is not very good sign. But i am now happy because i know that CPU-Z was ok and was correct about my Cpu speed, now i am @ 3378Mhz, 1,300 V (Wprime 1.55=24,119 sec) and it seems to be stable, so at last i am doing real OC , really thank you guys that you helped me to discover this blasphemy . I think about a new cooler for Cpu so i can finally reach some good clocks.
By the way, if you have some info about non-official bios for Gigabyte 945GZM-S2, rev. 2.2 i would be amazed, but so far i haven´t found any better bios for my MB.
Thank you again for helping me!