Honestly having the asus bio's will not help you much at all.. I would just push volts to the card oc it and call it a day. If you mess up the bios with flashing it, you may have to reflash it BLIND or with a spare card and that's not easy to do IF you don't know what you are doing. Also having the stock cooler will not help much, as these cards run REALLY hot.
( the asus top bios files can't be found here http://www.overclock.net/8848266-post5.html
But if you insist you're going to need a few things.
1. a flash drive
2. HP USB Disk Storage Format Tool - v2.1.8 http://files.extremeoverclocking.com/file.php?f=197
3. Windows 98 boot files http://files.extremeoverclocking.com/file.php?f=196
4. Boot to flash drive and flash away
atiflash -p -f 0 master.rom
atiflash -p -f 1 slave.rom
Again, I have done this in the past and was not able to oc any further than my stock sapphire bios.Edited by freakb18c1 - 10/6/11 at 1:28pm