Yes, this board is not stable, and I am doubting any bios will fix it. Voltage regulation is poor. With my board I use Everest Ultimate as it gives very accurate temperatures and voltages, and has an excellent stability testing module in the TOOLS menu that will run the CPU (all cores) and memory at max 100% load to verify stability..
I use Crucial Ballistix PC8500 memory (2.2v) and this board absolutely hates this memory. I have had headaches since day one. This is what I did to get it stable.
I know you have different memory but give these settings a try as it may help, as I ran the statbility test for over 30 hours with no problems using a Q6600 G0 and 4GBs of PC8500.
Load Bios F2. I know, but F4G stinks.
Use CTRL-F1 and go to the M.I.T. section Listed in order on the bios page:
Auto
8X
ENABLE
400
AUTO
DISABLE
2.5
1000
OPTION 1
EXTREME
MANUAL
5
6
6
18
3
3
6
42
AUTO
AUTO
AUTO
MANUAL
+0.3V
NORMAL
NORMAL
NORMAL
1.41250V
1.32500V
The bios sets default memory voltage around 1.8-1.9. The +0.3 brings the memory upto 2.27V (read this in Everest on the sensors page for the 2.5V reading. The voltage will drop to 2.21V under 100% load. This is poor voltage regulation.
The VCore volts, if set at 1.41250V, will give the CPU 1.37V (read this in Everest on the sensors page for the CPU Core reading. The voltage will drop to 1.31V under 100% load. This is poor voltage regulation.
My overall view of the board is it really is subpar and way overpriced. I would think 79-89US would be fair as it is not a quality product, has poor voltage regulation, and a lackluster bios (no viewable voltages is a poor design and a bad move by Gigabyte). I doubt the voltage drop issues can be addressed by a bios mod. And being at version F4G, and still all these issues, they can not fix the problems. How long do you have to wait for a good stable bios?
I was hestitant to change the memory voltages as you, because I was not sure where the voltages were defaulting to. Also bios F4G is no good for my Crucial PC8500, and finally got a stable system by reverting back to the final F2 bios, with the above M.I.T. settings.
Good luck
Dave