Yah need to drop your HT link to x4 and drop your memory ratio from 400 to 333.
That will give you enough *headroom* to go 14.5x242MHz or 3.5GHz+.
That will slightly OC your RAMs to 807MHz, and your HT will be running 4x242MHz.
If you drop your memory ratio to 266 and your HT to x3, I suspect you can run 13.5x280MHz for 3.8GHz (with good cooling) and your RAMs will be running 2.66x280MHz, or 745MHz.
You could try the clock at 300MHz - LOL - but that might be pushing it a little too far. You will return your RAMs to spec 800MHz if you manage to do so. (Hint: You might want an extra fan blowing on your FETs
I love Gigabyte (not a big fan of the nVidia chipset, though)