Fired up all the lights, no fans. Passive cooling only. Within half an hour the temp of the sink, measured behind an LED, was pushing 120 deg F., so I connected the fans. (These are Zalman ZM-F2, which are 2500 RPM @ 12V. Pretty quiet, just $5 each.) I've got 'em wired to a 9V wall wart, so they're really just loafing.

I watched the temperature drop back down to ~100 deg F. in 10-15 seconds. It was like you dipped the thermometer in cool water. :thumbsup:
[attachment=o214262]

Right now I've got just one fan running. They're kinda mounted diagonally, and I've got the thermometer as far away from the fan as possible, and right behind an LED--a worst-case scenario. Temp's are holding right at 100 deg F. with just the one fan running @ 9V. [attachment=o214263]

Probably the way to do this is wire the second fan to a thermal switch on a separate power supply as a backup.

[attachment=o214264]