I have looked but really cannot find anything that can help me decide on what size UPS I need for my new computer I am gonna build. I was hoping to find some sort of configurator that could help me so I thought I would ask you all.

Here is my parts list and I think the Power Supply Draw is the most important (I would think)

Antec 850W PSU
AMD Phenom X4 965 125W Processor
The rest of the computer is pretty much standard with 8GB ram and will have 3 - 4 hard drives in there. I have 2 19" LCDs and a printer, Router, DSL Modem I would like to protect too from an outage. Let me know if you think you need more than that.

I think a 450 - 600VA UPS will do and I currently have a 300VA one but it is like 9 years old and the battery is shot so I figure I should replace it. This PSU is about 400W more than my old one and think the computer will have more of a power draw. I liked the automatic shutdown of the computer feature so I definitely want that again and probably would stick to APC or Tripplite as my first choices. I do not want to get one that too small but I do not want to spend a whole lot of money on a bigger one than I need.

Thanks in advance.