The Verdict
AMD's aim in designing the Radeon HD 4870 X2 - aka R700 - was to architect the world's fastest single-board graphics card - a title that's been in NVIDIA hands for a while now.
Leveraging the strengths of the RV770 architecture, AMD fits two Radeon HD 4870 1GB cards on to a single PCB, CrossFires them internally, and sticks a heavyweight cooler on top.
Naysayers may argue that the means by which AMD has managed to gain performance leadership is by somewhat inelegant CrossFireX, but who cares when it's invisible to the system, spitting out ridiculous framerates along the way?
The end result is a card whose specifications far, far surpass anything we've seen in retail form before: 2.4TFLOPS of compute power. 230GB/s bandwidth, and 60Gtexels/s bilinear filtering.
Our performance evaluation shows that the HD 4870 X2 only comes into its own when the resolution is cranked up to 2,560x1,600, along with serious image quality; anything lower and it's sat there, twiddling bemused transistors.
Such is the performance lead at the WQXGA setting, that it's over 60 per cent faster than the previous champ, GeForce GTX 280, in both Race Driver: GRID and Call of Duty 4: Modern Warfare. A 50 per cent lead in Company of Heroes: Opposing Fronts and 30 per cent advantage in Enemy Territory: Quake Wars is nothing to sniff at either.
Can, whoop-ass, ouch all come to mind.
What can NVIDIA do to topple Radeon HD 4870 X2 2GB? It'll focus on its Cuda environment and PhysX support, but those are almost incidental features - limited to a few games - to the gamer who craves lustrous framerate above all else.
We'll have to wait for the GTX 200-series to go on a process diet, to 55nm, and then, just perhaps, we'll see a GX2 based on GeForce GTX 260. Until (and if) that happens, there's nothing to touch Radeon HD 4870 X2 2GB.
Contrary to the observations above, and appreciating how few readers have 30in, 2,560x1,600-capable panels, we'd lend a modicum of pragmatism and recommend most users look further down the chain, to Radeon HD 4870 512MB and GeForce GTX 260 896MB, as both GPUs provide excellent performance at 1,920x1,200 for almost half the cost.
In a perfect world the Sapphire Radeon HD 4870 X2 2GB would be as quiet as a GeForce GTX 280, ship with lower power-consumption figures, and use a single-die approach to eliminate the potential foibles of CrossFire rendering. The world isn't perfect, however, and the R700 does exactly what it was planned to do: framerate domination.
As a £330-£350 single-card solution that targets ultra-high-end gaming, the Radeon HD 4870 X2 2GB has absolutely no performance peer at all, based on our results, but, for most games, you really, really need a 30in monitor to make it worthwhile.
Then there's Radeon HD 4850 X2....
HEXUS Awards
The Sapphire Radeon HD 4870 X2 2GB is the fastest consumer graphics card in the world, bar none. Well, until someone launches a pre-overclocked model...