I've had my current PC since last May and I had the choice of buying up better parts to build a new one, but I'd like to avoid that if possible and just add another card to my system. What worries me is the power supply not being enough to handle the system. I've tried every PSU Calculator I could find and I keep getting different results. Some people and PSU calculators say that even 700W would work fine. Some people and PSU calculators will say that I would need a minimum of 950W-1000W. I would really appreciate some solid answers before I proceed.