It's worth noting that this recommendation has nothing to do with delivered power.... a 500W can handle most systems on delivered power. This has to do with tr

It's worth noting that this recommendation has nothing to do with delivered power.... a 500W can handle most systems on delivered power. This has to do with transients, the 3000 series cards have some massive transients that can easily trip OCP protection on powersupplies not designed for that kind of transient. A 700W powersupply is able to handle those transients much better than a 500W PSU is.