XBT Labs posted a review on the Gigabyte GTX260/275, HD 5870 Graphics Cards.

Let's say a few words about 5870 CrossFire. The time of ultimate victories in all tests is long gone. For the last several years we have seen occasional defeats caused by driver bugs. I already wrote that all graphics cards based on AMD GPUs suffered from the vertical sync problem in CoH - even though it was disabled in the driver options, it was still enabled in the game, so it was practically impossible to obtain frame rates above 59.9 fps. All RADEONs lose in this game. Not because they are slow, but just because a stupid bug does not let them reveal their full potential.

As for 5870 CF, this tandem puts up good performance. As we can see, it sometimes outperforms GTX 295 Quad SLI. Considering all innovations, including DX11, we can say that it's the most powerful tandem with the most 3D features these days (at the moment of publication).

Gigabyte GV-N275SO (GeForce GTX 275 SuperOverclock) 1792MB is a very interesting product. Our tests prove that the card can outperform even the more expensive GTX 285. Plus a certain stepping stone for future models, as this huge memory capacity is excessive today.

Gigabyte GV-N26SO (GeForce GTX 260 SuperOverclock) 896MB is no less interesting. It manages to catch up and outperform the more expensive GTX 275, operating at nominal frequencies. Certainly expedient.

Gigabyte GV-R587D5-1GD (RADEON HD 5870) 1024MB possesses everything of a reference HD 5870 card. Nothing more, nothing less. So you might as well read our conclusions here. By this time it has been the fastest graphics card with the most 3D features.