You might've heard us mention this new "AUSUM" mode a bit in our recent Sapphire HD 6990 4GB. If you missed out reading our Sapphire HD 6990 Technical Preview, I'd highly recommend you check it out to see exactly what it does, even if you just jump to page 3 which covers "AUSUM" mode and the Dual BIOS switch. Due to the fact we've already covered the Sapphire HD 6990 in quite a lot of detail, we'll just be getting straight into the specifications of the card when we flick that Dual BIOS switch to AUSUM mode. If you can't be bothered reading the Technical Preview and you don't know exactly what AUSUM mode does, we'll quickly just cover how you switch it on and the clocks it carries when on along with any other features it brings. So with that all said and done, let's check out the GPU-Z information and exactly what we're dealing with. AUSUM Mode Enabling "AUSUM" mode is done by nothing more than a flick of the switch. Like the HD 6950 and HD 6970, we have that little switch behind the CrossFire connector(s) that switches between two different BIOS'.