Thats cool Rage, I wasn't 100% which is why I asked for confirmation. So what did I calculate incorrectly? From your post it appears to be the assumption that the 3.33v and 5v rails are separate. Is the maximum wattage calculated using the 12v rail only?
Nope. There's a separate maximum power figure given for the +5V and +3.3V rails combined. You can see it on the Silverstone PSU sticker below. Image courtesy of HardwareCanucks