I think if it is a PCIe2 card only then it's OK? 150W from the pcie slot compared to 75w
Nope 300W is the limit, 150W from slot and 2 x 75W from the 6/8 pin power connectors.
Pcie1 was only 225W
However, pcie 3 was meant to come out next year but has now been put back a year to 2011. Perhaps pci-e ups the power limit to even more which would then allow this card.
Then again I don't beleive there will ever be GTX395 unless there is another die shrink.