Here are the official power requirements for the brand new ATI Radeon HD 5850 and HD5870 video cards.
ATI Radeon™ HD5850 System Requirements
PCI Express® based PC is required with one X16 lane graphics slot available on the motherboard
• 500 Watt or greater power supply with two 75W 6-pin PCI Express® power connectors recommended (600 Watt and four 6-pin connectors for ATI CrossFireX™ technology in • dual mode)
ATI Radeon™ HD5870 System Requirements
• PCI Express® based PC is required with one X16 lane graphics slot available on the motherboard
• 500 Watt or greater power supply with two 75W 6-pin PCI Express® power connectors recommended (600 Watt and four 6-pin connectors for ATI CrossFireX™ technology in • dual mode)
NOTE - These are the power supply recommendations for an entire pc system. I can't wait to see techncial reviews with power consumption results. I knew the cards were supposed to be more energy efficient than current generation cards.