bit-tech published a review of Sapphire's Radeon HD 4870 X2 Atomic

We find the Sapphire ATI Radeon HD 4870 X2 Atomic in something of an odd position. It is unquestionably the fastest single consumer graphics card currently available to buy -- our benchmarks prove this unequivocally. Its watercooling loop is also able to keep the GPU remarkably cool, significantly more so than a stock card and much quieter in doing so as well. The problem lies in not only the price, which borders on the ridiculous, but the knock on effects of putting such a high thermal output card into such a relatively small watercooling loop. CPU temperatures suffer terribly to the point that even a £10 aftermarket cooler will comfortably outperform it.

What this product is then, is niche. In fact, it's a niche within a niche. It's for those looking for the absolute fastest graphics card without the hassle of building a waterloop themselves and have money to burn. If you fall into this, admittedly small demographic, then the Sapphire ATI Radeon HD 4870 X2 Atomic is a great product that accomplishes exactly what it sets out to do -- it's the fastest consumer card in the world right now, is an absolute breeze to fit, and runs cooler than a stock card by a wide margin even under load.

If however you're like the rest of us who don't have the best part of £600 to spend on a single graphics card or even fancy being brave enough to try putting together your own watercooling loop, then this isn't such a success. Similar performance can be had at a much cheaper price point by either watercooling and overclocking a stock 4870 X2 (although you'll lose your warranty by fitting the waterblock), or by picking up a pair of GeForce GTX 260 (216) cards and running them in SLI. While respectively more difficult to install than and not as elegant as the Sapphire ATI Radeon HD 4870 X2 Atomic, you'll save a packet either way.

Sapphire's Radeon HD 4870 X2 Atomic