I have a gigabyte too, the dual bios is excellent. Easytune is ok, thats the software mine comes with, but its basic as far as overcloking goes. My gigabyte board has very limited memory options in the bios. I can increase the voltage a little bit, and fiddle around with timings but thats it. Only other things I can change are CPU FSB and multiplier plus a few other voltage settings. It also doesn't really like running my memory at 400mhz, but extreme overclocking aside, gigabyte make fantastic boards. Only reason I'm upgrading is that I would like Nforce 2 ultra, a bit more performance, and mess around with overclocking.
The Epox board suggested here sounds great. Because its nforce 2 you can alter clock settings while keeping everything else running separately at its deafult speed, ie PCI and AGP bus. I think this is what I'm having trouble with at the moment because I can't get my FSB above 180mhz (360) no matter what memory timings or multiplier I use. I also use corsair ddr 400. My athlon xp 2500 should be ok, but I think its to do with the fact that I'm also upping the AGP and PCI bus' when I'm increasing the FSB, and it doesn't like it! I'll have to take my chances with the lack of a dual bios though! I'll have to find that damn little jumper again!

For now id look at o/c memory & cpu as separate things - your FSB's might be able to go higher by upping the voltage, but check your temps and any crashes/failed boot ups.

If i were o/c your cpu id work out its normal speed (Mhz) then drop the multiplier a few notches and raise the cpu FSB up so that the total speed is the same - i kept dropping the multiplier/upping FSb till i got 200Mhz FSB, but i wa using Nforce2.
However, you must take care of PCI/AGP speeds - are there no divider ratio settings present to alter this?

Dual BIOS doesnt really come into o/c at all - its just a fail safe when flashing the BIOS. Most others just use the 'clear CMOS' jumper to undo

For now id look at o/c memory & cpu as separate things - your FSB's might be able to go higher by upping the voltage, but check your temps and any crashes/failed boot ups.

If i were o/c your cpu id work out its normal speed (Mhz) then drop the multiplier a few notches and raise the cpu FSB up so that the total speed is the same - i kept dropping the multiplier/upping FSb till i got 200Mhz FSB, but i wa using Nforce2.
However, you must take care of PCI/AGP speeds - are there no divider ratio settings present to alter this?

Dual BIOS doesnt really come into o/c at all - its just a fail safe when flashing the BIOS. Most others just use the 'clear CMOS' jumper to undo

Hi thanks for the post. I have upped the voltage but again the board is holding me back only allowing +5%/+7.5% and +10% increases which doesn't really give me the detail you need I think.
Even upping it to 10% doesn't solve the stability issues. Because of this I'm pretty sure that if I had Nforce 2 and were able to lock the pci/agp bus (no my board is Via and so doesn't have a divider), I'd get some better results as it seems to get unstable at anything over an fsb of 180, no matter what the multiplier.

I've found dual bios to be good, but my board has no cmos jumper. While 90% of the time the board seems to solve the instability by reverting back to the previous bios settings, it can sometimes take 5 or 6 reboots to do this. I certainly won't miss it and I'd much prefer to have a little jumper thing anyway!