How much power do I need?

[Varone]

Antec P182B
Intel Core 2 Duo E6750 Conroe
Asus P5K Premium (TBC)
4GB (4x1) Corsair PC2-8500 Dominator
2x BFG 8600GTS OC2 256MB (720Mhz)
150GB Western Digital Raptor X
400GB Western Digital Caviar

Originally I was going to opt for a single video card and so a 530w PSU seemed fine but I recently decided to going for a couple of 8600GTS' and am concerned that the power drain will be too high. I haven't gone for a dual card setup before so any help would be appreciated.

A specific PSU recommendation would be nice too, but it will need to fit in that cage on the P182 and be relatively quiet.

 

[Varone]

The benefits of an extra 256mb in a single card on the 8600GTS made no difference to performance but a second card both running at 720Mhz, and 256mb on each card running at 2200Mhz seemed like a good idea. For under £250 on cards it seemed like the best option. Do you beg to differ?

 

[Varone]

Thanks for the input guys. I think I'll go for that 8800GTX! Is the cooler pretty loud and if so are there any third party improvements?