The unit carries no approvals for SLI or Crossfire on the packaging or in the user manual. The Nvidia website however, does list the Toughpower 650W (Model W0104RU), the one supplied to me is the Toughpower QFan 650W (Model W0163RU), so please do not confuse the two. The W0163RU is a relatively new addition to the power supply range according to the Thermaltake website and, at the time of writing this review, carried no certificates for SLI or 80 Plus. It would come as no surprise to see this power supply certified for both SLI and 80 Plus some time in the near future. With excellent DC load voltage regulation, good DC quality and efficiency of over 80% I would highly recommend the Thermaltake Toughpower QFan 650W power supply. I have no doubt it will easily power most mid to high end systems with a single graphics card but if you are considering a dual card set-up do your research first and ensure compatability with your intended system.