Quote: Originally Posted by bobkn
Sapphire wants a minimum 400W power supply for their version:
That is a CYA by all video card manufacturers to take into account the number of low quality power supplies out there. They know full well that the card and system don't need a 400 W power supply, but we have all seen the specs on some of those low cost/quality ones, and a lot of the lower wattage PSU's are even worse.
Considering the low power usage of a card like that HD 5570, a good quality 300-350 W power supply is more than enough in most cases. And no that 250 W Bestec won't cut it.