Try your luck ,if it s a new revision it will work most probable.
3,5 Ghz on paper as it will be able to work higher than the factory CPB 4,1Ghz in daily use with small tweaks
It will reach the first turbo state at 3,8Ghz most of the time by default.
Get some Athlon/Phenom 2 CPU from a friend and update before reinstalling the FX 6300 ,if you have issues.
Get a minimum rev 3.0 with this boards as the prior ones will not receive BIOS updates ,old AWARD BIOS.
If it s old send it back to the reseller,get rev 3.0.