I'm new to OCing as well. I recently put together a rig consisting of an Iwill KK266 mobo (nonRAID), and a 1.2G 'C' Tbird (AXIA 9). For hsf I've got a ThermoEngine anodized w/ 7k fan... Currently I'm at 1380MHz (and still looking for more heh)
What I've done was mostly trial and error- every problem I encountered was easily fixed by clearing CMOS a couple of times or just going back into BIOS and fiddling some more, but I will tell you this- there IS a difference when you increase the voltage. I don't know about Abit's board but with the Iwill (which I believe are very similar boards) there are numerous incremental voltage adjustments you can make using both BIOS settings and with jumpers on the board itself. I did notice though, that if I reach a multiplier/FSB setting that was slightly unstable, it would became stable if I increased the voltage.
Just don't be an idiot like I was and try to go for a crazy FSB setting right off the bat (yeah I did attempt to jump from like 137 X 9.5 to 166 X 9.5 when I first started tweaking... DOH had to clear CMOS after that)
I am real happy with Via Hardware Monitor too- every time I try a new multiplier/FSB/voltage setting, I boot up, run a Q3Arena, then do a quick check on the temperature with the ViaHM. Everywhere I've read said to be careful when you creep into the mid 50s degrees C range, and I've never gone past 47C (just yet). Oh and that's another thing, every time you try a new setting, go straight to a game or program that will stress your hardware somewhat. Q3Arena is great because it's so easy to get into it and jump right out as well.
Hmmm consider that this is advice from one newbie OCer to another also LOL
Redstar