The Zalman ZM850-HP has good efficiency in 230VAC but lower performance in 120VAC. It also suffers from poor 12V DC output distribution, what with the 6x +12V rails at 18A~20A each. It's also a discontinued unit.
I can't answer for sure if this PSU will be good enough for your rig as you did not list your PC specs.
In any case, there are a lot of other PSU's out there that are more reliable and more efficient than this.
Review here: https://www.techpowerup.com/reviews/Zalman/ZM850-HP/ and here:
http://www.anandtech.com/show/2558