Graphics card maker BFG has added a 1200W power supply to its lineup, the EX-1200 has four +12V rails and is rated at 1200W continuous at 40°C. It promises an efficiency of at least 80 percent, even at loads of only 10 percent. Full specs can be found over here.
BFG Tech has taken a whole new approach to computer power supplies with the EX Series. Most power supplies are inefficient at lower loads, making it difficult to plan for future expansion while maintaining a green initiative. By using Frequency Conversion technology, the EX power supply can actually emulate virtually any size power supply and therefore be at least 80% efficient, even with loads as low as 10% of the unit's maximum capability. EX power supplies have the lowest minimum load requirements and the best +5VSB efficiency on the market. BFG Tech uses all Japanese capacitors for longer life and gold-plated pins for improved conductivity.