Overclocking

While the card’s stock performance is identical to that of any other stock Radeon HD 4890, the big draw for the Asus is its overclocking abilities thanks to the inclusion of the voltage tweak option in Asus’ Smart Doctor software. This is where the card really gets to show its stuff and we’re pleased to say we were enormously impressed with how much extra we were able to squeeze from the card.

We first used only Asus’ overclocking software, the use of which is, uniquely, covered fully by the card’s warranty, making for care free overclocking without the threat of blowing up your GPU without an RMA fall back. Having previously only achieved 965MHz from the RV790 core and 1,100MHz (4,400MHz effective) from the memory of a reference HD 4890, we were keen to see if the card could reach 1GHz with a little love from the voltage tweak, a feat it achieved easily using a 1.4v vcore.

We eventually topped out in Asus’ own overclocking tool at a 1GHz core clock and a memory speed of 1,111MHz (4,444MHz effective), a huge increase of 175MHz (17 per cent) and 136MHz (544MHz effective) respectively, accomplished using a 1.437v vcore. However, from our past experiences with the Sapphire Radeon HD 4890 Atomic we knew the core could go higher still, and successfully pushed the card even further using RivaTuner, which is able to run alongside Asus’ Smart Doctor. Our final top overclock was 1025MHz core and 4,444MHz effective memory, resulting in even bigger jumps in performance than what we saw from the 1GHz Atomic, and all from a sub-£190 card!


S.T.A.L.K.E.R is well known as a highly demanding game that'll take advantage of any increase in a graphics card's core, shader or memory clock speeds, and that's certainly the case here. With out maximum stable overclock applied the Asus Radeon HD 4890 is able to up it's minimum frame rate from a borderline playable 26fps to a much smoother 33fps, with a similar 6fps increase in average frame rate too.


Our massive overclock has a clear impact in Call of Duty: World at War as well, increasing the minimum frame rate by close to a third and the average frame rate by a good eight frames per second.


Fallout 3 is extremely memory bandwidth hungry and our healthy overclock has a big impact, increasing average frame rates by roughly eight per cent.



Crysis is still one of the most demanding titles out there and the Asus' monster overclock offers sizeable improvements. Minimum frame rates rise by over 18 per cent, with average frame rates up by roughly ten per cent - not bad dividends for a few hours of patient overclocking!