Does not require any additional power supply. I thought when installing, darn, where I closed my the 6pin power connector. Installed on PC, and lo and behold, running like hell !!!! Had previously ne 9600GT. After 8 years as you can before his PC what good do! Have NEN i5 2500K and the graphics card and feel my computer now as "Up to Date". Games all in high resolution. For 146 Euro, I now also have a quiet PC. Pleasant in all respects.