Can't you just use a flash program to make a backup of your current BIOS, and edit the info with one o' those BIOS editors? No first-hand experience here, but I'm fairly sure I've seen it talked about around here. You just change the Vcore to 1.6 from 1.5 or something. Maybe you could try 1.7?
If that's not feasible, surely someone out there has figured out how to do the hardware Voltmod? Made a massive difference to my 9800Pro's overclockability
. If you're not worried about blowing it up then a little play with a soldering iron shouldn't be overly scary to you.
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A64 3200+ Winchester @ 250x10= ~2.5Ghz, ~1.41 Vcore
1Gb @ 209Mhz, 2T, 3-5-5-10
Voltmodded Sapphire 9800Pro @ 450/350 w/ modded VGA silencer 3.