Overclocking, Thermals and Consumption
Sapphire is the first company to come out with an overclocked HD 5970 card, although the overclock is only slight 10MHz more than reference 735MHz. GDDR5 memory runs at 1010MHz or (4040Mhz effectively) compared to the reference 1000MHz. Of course, HD 5970 will take even higher clocks, and as a proof of that AMD ships OverVolt Utility tools with overclockers in mind, whereas Sapphire ships it under the name of RedLine Overclocking/Tweak Utility as they use a different interface.
It's a simple set of tools which, as the name suggests, is used to increase GPU and memory voltages. Below you see a snapshot of RedLine tool and we moved the sliders all the way just to show you how far you can go. It's best to use it combined with Catalyst Control Center Overdrive where you can alter clocks as well as the fan's rpm. Pushing the card to 850MHz and the memory to 1250MHz is a piece of cake and it results in 17% better gaming results.
The following picture shows GPU-Z, which reads reference clocks and those used by Sapphire's HD 5970 OC.
Idle temperatures are pretty good and the card runs at about 60 degrees Celsius. During operation, the new Vapor Chamber-based cooling shows why it got the job and cools the core to below 90 degrees Celsius. Interestingly enough, this didn't significantly reflect on temperatures (only a few degrees Celsius), but the card was much louder, almost unbearably loud.
Regardless of the improved performance, power consumption didn't go much higher compared to the previous generation. We've said that HD 5970 draws up to 294W, which is great when considering that one HD 5870 consumes 188W or that one HD 4870 will draw 160W. AMD finally addressed idle consumption and AMD claims the HD 5870 will draw only 27W and the HD 5970 will draw 51W.
The HD 5970's idle consumption is excellent. The core downclocks to 157MHz and the memory to 300MHz. Our testbed drew up to 487W, which isn't much considering the performance, but is still 100W higher than when we use the GTX 295. The HD 5870 required up to 335W, which is pretty close to the HD 4890, which is significantly slower.
Idle operation in our test rig consuming about 115W, whereas the same setup with the GTX 295 resulted in consumption of about 90W.
Sapphire Radeon HD 5970 OC is currently the fastest gaming card you can find. Let us recap –Radeon 5970 is a dual-GPU card with two Cypres GPUs, which Sapphire overclocked by 10MHz from the reference 725MHz. The card packs 2GB of GDDR5 memory, also overclocked by 10MHz from the reference 1000MHz (4000MHz effectively). The Cypress GPU comes from AMD's Evergreen family of products and features DirectX 11 support, which makes such an investment pretty much future-proof and users who buy it won't need to upgrade their graphics for a couple of years at least.
This card will take anything and any game and always provide enviable performance, even at the highest resolutions. Catalyst driver support is excellent and there are no major problems with this dual GPU Card, so the closest you'll get to a problem is when buying a game that doesn't support Crossfire. If you have the means to buy this card, and you're scared of any notion of setting up Crossfire, don't worry as Crossfire is enabled by default and all you need to do is stick it in the PCI-Express x16 slot and install the driver. System compatibility is not an issue as the two GPUs communicate internally via a Crossfire link. Furthermore, the card is 31cm long, so you might want to check that you've got sufficient room in your case.
The Sapphire HD 5970's fierce rendering capabilities make even more sense with the new Eyefinity technology, which allows for three monitors on one graphics card, and note that the number of Eyefinity-supporting games is on the rise.
As far as noise, consumption and thermals go, Sapphire Radeon HD 5970 passes all the test with pretty nice grades. The card isn't too loud during gaming, and although it occasionally can get a bit loud, it's understandable as two Cypress chips are no easy task for one cooler.
Once again in this everlasting game, AMD dethrones Nvidia on the "king of perfomance" seat, but it seems like Nvidia won't fight back anytime soon. In case your holiday shopping list includes Sapphire HD 5970, you should know that you'll also receive two additional gifts – Battleforge and Dirt2 games.
The only reason not to buy this card, if there is one, would probably be the saucy price of over €600. Unfortunately, the cards are pretty limited and it instantly shows on the prices, but as soon as availability issues are solved, expect to see it priced more towards the €500 mark.
Sapphire HD 5970 OC is a card one instantly falls in love with, and we have no doubts that you will too if you buy it. Yes, the price is a bit steep but don't forget that you're buying the world's fastest graphics card, and such cards are never cheap. With that in mind, and the fact that this card will have you set for a long time, we welcome the new performance king to the market with the "Fudzilla Recommended" award.