This FPS Booster X3 5.25-inch drive-mounted power supply is great for gamers with multiple PCI Express graphics cards or video editors that use a lot of hard drives. The power supply (PSU) fits into a normal 5.25-inch slot on the front of your machine, but has a two-pin power connector cable that goes through your machine, out the back through an empty PCI slot, and into the wall.
The PSU outputs 300W to supplement or replace an existing power supply. In their setup, The Register was able to power two X1900 CrossFire cards using just the X3 with no problem. It’s available for £61, or $116 for us Yanks.
FSP Booster X3 GPU-friendly power supply [Reg Hardware]