As you know we usually recommend using the BIOS to OC, though AMD OD is a very useful tool. What is especially good about it is you can set up your OC in the BIOS near the wall you may be reaching. Then boot to windows and try to push further with AMD OD. Sometimes you can get those few more Mhz you wouldn't normally get because you can't get it into winders. We recommend using the BIOS because it's a bit more stable and it is useful to understand your BIOS when OCing. Using AMD OD is great especially because you don't have to restart every time you want to make a change.
Also, I may have told you this before but it's a tidbit I learned when I started going sub ambient. At some point even though you may be no where near the chips "recommended Max temps" the chip may not be able to take any more voltage unless you get it colder. For example, even though the chip may only be at 35-40c it may be too hot even there for it to be stable with excess voltage. I say this because you mentioned you were going to try 1.6v, which may or may not be too much. Another thing is sometimes you need to sneak up on it with voltage instead of hitting it with the Caddi Daddi sledgehammer of voltage. This sneaking up on the voltage also implies on the FSB. Sometimes when I testing a chip and I know it can do for example 260 Fsb with 13.5 multiplier at X voltage. If I just set it that way it will crash every time. If I set it at say 250 Fsb and 13.5 multi and then use the AOD Od while in windows to up my Fsb to 260 it doesn't crash. Warning, just remember when really pushing the voltage the magic smoke may leak out at any time.
