Need some assistance choosing a PSU

So after getting many opinions and using online PSU calculators, I've decided to ask the community one last time what wattage power supply I'm going to need.

Here's my rig I'm building:

AMD Phenom II X3 720 2.8GHz Socket AM3 95W Triple-Core Black Processor

ASUS M4A78T-E AM3 AMD 790GX HDMI ATX AMD Motherboard

OCZ Flex EX 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800)

Western Digital Caviar Black WD5001AALS 500GB 7200 RPM SATA 3.0Gb/s 3.5" Internal Hard Drive

2 ATI Radeon HD 4850's in Crossfire

I will also have a CPU cooler, a few case fans, keyboard mouse, and a few other USB peripherals plugged in.


Online calculators have given me recommendations of anywhere from 450w to 650w
Coworkers have said about the same.

The one I currently own is a 700w Rocketfish PSU and I'm wondering if it will do the trick or if I'll need more or less power.

Thanks for any input!

Check the 12v amp rails. They should total 40 amps or higher. If not, I would get a corsair or pc power and cooling. They have high 12v amp rails.

It should be fine since it has 700w im sure the rails are going to be decent for at least 2 4850.