A while back we published a guide, with some help from AMD and macci, on how to overclock Radeon HD 2900 XT when running two of them in CrossFire mode. The software method we described there is a bit tricky and takes a while perform if you’re new to it. After doing it a few times it’s not that bad though. The second way to do it is to flash the cards with new BIOSes to access to higher frequencies. However not everyone has access to these BIOSes, but forum user super dank came up with alternative then; Hex editing your BIOS. All you need is the ATI flash tool and a Hex Editor, and all of a sudden you can set whatever frequencies you want. Be careful though, if you edit the wrong data you will kill your graphics card.
:: How to Modify You HD2900 BIOS Clock Frequencies by Hex File
