Gateway power supplies still proprietary?

Hackworth

As someone who has built his own computers since 1987, this deal is just too
good to pass up:

Gateway FX7026 Core 2 Quad Q9300(2.50GHz) 4GB DDR2 640GB NVIDIA GeForce
8800GT
http://www.newegg.com/Product/Produc...82E16883113058

I need to replace my son's gaming system, and this seems like a great option
for me, especially since I just don't have the time to mess around with
building PCs from scratch these days. The only concern I have is the chincy
400w no-name power supply. I have some extra beefy power supplies that I
could easily swap out in place of the one that ships with this system , but
I need to know if Gateway still uses proprietary power supplies and
motherboards. Will I fry the system if I swap power supplies in this box?