Sapphire Radeon HD 5870 1GB GDDR5 is a card we'd wish for ourselves. The Cypress GPU's performance is already excellent, without its potential being utilized to the max, which makes it a potential blockbuster. Unfortunately, the HD 5870 won't really shine until the first batch of DirectX 11 games and Windows 7 are here. On the other hand, buying this card means you're investing in the future, and this card is definitely a tough nut to crack for almost any card in current games, not to mention future titles.
It comes with 1GB of speedy GDDR5 memory at 1200MHz (4800MHz effectively) and the Cypress core at 850MHz. Sapphire HD 5870 shows that it has what it takes to handle anything you might throw its way, and although the dual-GPU HD 4870 X2 has an upper hand in many tests, the HD 5870 is always close. So pick your favorite feature that makes this card worthwhile - the fastest single GPU card, DX11 capable, significant decrease in consumption, more quiet operation, and the list goes on.
On the other hand, the card is a bit pricey but the upcoming HD 5850 will surely change that. Besides, you can always wait for the price drops. Be it as it may, this card is the fastest single-GPU offering on the market, and currently the only DX11 supporting card, and if you're looking for any of these two things then Sapphire HD 5870 is not only the right, but only choice you currently have.