thankyou at all, i've resolved my issue.
The F2 code on diagnostic display is referred to the Bios version and the alert that the bios doesn't support CPU.
Today i've take from a friend an AM3 CPU and flashed bios to F6, now all works perfectly.
MB Name: Gigabyte Technology Co., Ltd.GA-990FXA-UD7
BIOS version: GA-990FXA-UD7 F6
CPU Name: AMD FX(tm)-6100 Six-Core Processor ***************
Memory information: Total physical memory 8173 MB
OS information: Windows 7 Ultimate 64 Bit version
This CPU isn't the best, but he works good