So to set this straight, your OCZ supplies 500W with a total of 36A across it's dual 12V rails. An 8800GT SLI setup requires at the minimum a 450W power supply with 24A on the 12V rail. Your PSU exceeds that by 50W and 12A, it doesn't sound like much, but it's plenty.
ah i see.
Then off to get another 8800GT off of newegg.
i kind of want to get another eVGA, but then again i also want to save money and get the XLR8 because it looks cool...