Brand pirate.
1st off: It's a con power supply to begin with with only 220W on the +12V rail. The only way you can get 500W out of that thing is if you add up all of the rails... which isn't a possible way to load up a PSU.
2nd: It says it's a ATX 2.03 PSU, but it has a 20+4-pin main connector. That was implemented in ATX 2.2, which launched in 2003. 3dfx was gone as a company and the brand then became an asset of Nvidia... and Nvidia is not licensing the 3dfx brand to anyone; certainly not some cheap PSU company selling crap in South America.
