Sapphire Radeon HD 6990 4GB Video Card

By using the AUSUM switch on the spine of the card you can take the card from its default 830MHz clocks to the over driven 880MHz at 1.175v. AMD gives the enthusiast/overclocker the ability to see a speed bump with nothing more than flicking a switch. Truth be told it works and shows a slight FPS increase when you need it. On the other hand we have the way we normally do things and used a combination of tools including Sapphire's TRIXX utility to bump the clocks up. The core was bumped up to an aggressive 950MHz to start with and was a bit to much for the card and voltage capabilities of 1.175v. Reducing the clock speed to 940Mhz was met with success and is the final clock speed I was able to achieve. This is an increase of 110MHz over the 830Mhz base speed on the cores. The GDDR5 memory scaled quite well and was able to reach a lofty 1473MHz before causing issues in the gaming tests. 1500Mhz was my target as the 6970 seems to reach these speeds at will but a 223MHz improvement is well worth the effort.