AMD ATI Radeon HD 5970 graphics card

AMD’s ATI Radeon HD 5970 graphics card combines two Cypress GPUs in one large — and powerful — package. Though hot and power-hungry, the graphics card can easily surpass the competition in most circumstances, making it a must-have for any hardcore gamer.

AMD’s previous Cypress GPU graphics card, the ATI Radeon HD 5870, definitely impressed us. However, looking at what two of these processors are capable of instils us with a sense of awe. The ATI Radeon HD 5970 uses 4.3 billion 40nm transistors and for a total processing power of 4.64 teraflops. The two cores run at a standard clock speed of 725MHz each, and are accompanied by 2GB of GDDR5 memory running at 1000MHz — 4 gigabits per second of bandwidth.

All of this means the graphics card isn't frugal when it comes to power consumption. While it consumes a reasonable 42 Watts when idle, the ATI Radeon HD 5970 reaches a whopping 294W at maximum power; that’s 114W more than the single-GPU ATI Radeon HD 5870 graphics card. The card is compatible with CrossFire multi-card configurations, though you’ll need a minimum 1000W power supply to even consider running more than one card in the same PC.

The AMD ATI Radeon HD 5970 measures 317mm from end to end, making it a stretch for most ATX cases; it wouldn’t even fit into an Antec Skeleton enclosure. Like the ATI Radeon HD 5870, this graphics card has an all-encasing shroud with just one fan to cool both GPUs. It manages to keep things cool at 47 degrees provided the processors are idle. Put the card under pressure, though, and temperatures shoot to 77 degrees, even in open-air setups.

The video card is compatible with DirectX 11, which is slowly gaining traction with the release of games like DiRT 2. The ATI Radeon HD 5970 is also compatible with AMD’s ATI Eyefinity technology, which scales performance across multiple monitors. Technically, the technology can support up to six monitors per GPU, or 12 displays for the ATI Radeon HD 5970. However, most initial versions of the graphics card will have two DVI ports and a mini DisplayPort, so it will only output to three monitors simultaneously without extra adapters.

You’ll be able to use the card’s grunt for more than just games, thanks to AMD’s ATI Stream technology. Like NVIDIA’s CUDA architecture, ATI Stream offloads processing power from the PC’s CPU to the graphics card, which can potentially speed things up. The technology is still quite young, but can be handy in applications that utilise OpenCL or DirectCompute, as well specifically optimised software like Cyberlink’s PowerDirector 8.

We ran our benchmarks tests on a Vista 64-bit machine running an Intel Core i7 965, 6GB of DDR3 RAM and a Western Digital VelociRaptor (WD3000GLFS) hard drive, installed in an Antec Skeleton case.

Though the AMD ATI Radeon HD 5970 graphics card can’t claim the ultimate performance crown in Futuremark’s synthetic benchmarks, it’s undeniably faster when it comes to real-world gaming. Not only is Crysis playable at high resolutions (for once), but other DirectX 10 games like Far Cry 2, Lost Planet and Call of Juarez are miles ahead of the competition.

Given that these results were delivered at stock speeds, the graphics card’s potential when overclocked is certainly astounding. AMD even encourages aftermarket overclocking by bundling the ATI Overvolt utility, which allows you to directly change GPU and memory voltages without limits. For the inexperienced, the driver’s ATI Overdrive utility has an auto-tune option to overclock your graphics card with fewer risks. In either case, however, AMD’s warranty won’t replace your card if it accidentally catches on fire.

AMD alleges that the ATI Radeon HD 5970 is the “fastest graphics card in the world” and we’re inclined to agree. If spending $850-$1000 on a single PC component seems reasonable, the ATI Radeon HD 5970 is definitely the highest performing choice.

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