You are correct, the enclosure that I used was an old external CD-ROM housing. Computer components are designed to run off of 12V DC and 5V DC so the enclosure had the appropriate power built in. If you dont have one handy you can purchase a variable "Wall-wart" from your local big box store. While it is unplugged, set it to 12V DC, cut the end of the cable and wire the power lead from the fans directly to that. Please be careful with modifying the power supply as you can be electrocuted.