So, can I use this or what?

[fortyways]

http://www.newegg.com/Product/Product.aspx?Item=N82E16814102735

I want this. My power supply is a 380Watt Antec EW. 27 amps on the 12V rail.

I can do that, right?

The X700 uses less power than an 8500 GT right? That's what it's going to be replacing.

Speculations are welcome, as I can't seem to find the power requirement anywhere.

 

[Deviousmind]

You should be fine with that mate just, or if you want try this, dont worry about it saying asus is good for most
http://support.asus.com/PowerSupplyCalculator/PSCalculator.aspx?SLanguage=en-us

 

[ceewi1]

The X700 actually uses a little more power than the 8500GT, but that PSU will handle it easily.