I haven't messed with anything other than F4 because it's doing exactly what I want. I did have POST problems at 3.0 Ghz / 333 FSB and stock volts tho, which I attributed to the CPU volts not being quite enough for a happy POST. My P35-DS3R runs at a very low voltage at stock settings, around 1.18 load, which is obviously pushing your luck at 3 Ghz lol. Was completely stable in Windows testing, oddly though.

I would suggest a touch more CPU voltage and see what happens.

As for Q6600 and P35-DS3R being a good combo, well it's working fine for me. It's definitely more fun to work with than the 965P-DS3 I also have. However, that could be because of my E4300's dislike for high FSBs. I had to reset the BIOS about a zillion times due to infinite reboot cycles when trying to get that setup where I wanted it.

The vDroop of these Intel boards, and these gigabyte boards in particular, is a very odd phenomenon. But it's not really an impediment unless you want to go super high volts, probably above 1.50v by sensor.