Here is a nice site to calculate how much wattage you are useing Link
What people need to realize though is that you need to look at your 12V rail and how much power it can put out compared to how much you'll be using. You never want to run a psu at 100% and most people will not use all available power from the 3.3V rail, so that lowers the advertised number by quite a bit.
Wow thx for the flame job. I post a site so some pepole could calculate approximatly how much wattage they are useing. And you go into how important the 12v rail is and how you shouldnt run your psu at 100%.