I have the MSI 790FX GD70 motherboard and I can overclock fine upto a max of 3.875ghz by changing just the multi and voltages.
When I tried to change the fsb using bios version 1.3 if I went more than a couple of steps above stock then it wouldn't even post. So I updated the bios to the latest 1.4 and finally it would boot with an increased fsb, even past post and got into windows with an FSB of 247 and a 15x multi.
So I thought great then I ran CPU-z and found I was in fact running on the desired 15x multi but the fsb was still at stock 200.
Bios says I'm at the settings I set, post says I am but why does it all change when I get into windows.
I know several other GD70 owners aren't having these issues.