Now ATI is here with its next generation of graphic cards ATI Radeon HD 5870 and HD 5850 boasting of DirectX 11 support and ATI Eyefinity technology are now available in the market, these video cards support upto 3 monitors and resolution upto 2560×1600 per display, 6 screen support will eventually come out in November with a new version of 5870 graphics card with 6 mini display ports. HD 5800 series of graphics cards also supports dual, triple and quad ATI CrossFireX multi-GPU technology.

ATI HD 5870 and 5850 GPUs are developed on the advanced 40nm fabrication technology containing massive 2.15 billion transistors and additionally the streaming processor units, texture units and ROPs are almost doubled in comparison to ATI 4870 and 4850 GPUs respectively. My 6 months old Dual Sonic 4870 graphics card is already feeling older, I might even sell it to make way for new GPU chips, the performance that these cards provide and their price point makes them the only graphics card you should buy if you are in a market for a higher end graphics solution as of now.
Power consumption
Apart from double performance ATI has attained another feat in power consumption, 5870 graphics card consumes only 27 watts at idle and 188 watts at full load when used with single display whereas 4850 consumes 27 watts at idle and 170 watts at full load with single display, with two displays the idle power will be doubled.

Price of ATI HD 5870 and HD 5850

The new video cards are priced at sweet $259 for HD 5850 and $379 for HD 5870, the prices will come down a bit once ATI releases new cards in November or if NVIDIA comes out with its lineup of DirectX 11 cards.
India Price would be around Rs 17,000 for HD 5850 and Rs 25,000 for HD 5870
Full Features of HD 4870 - AMD Website
Full Features of HD 4850 - AMD Website
ATI Radeon HD 5870 Review