MH fixtures: are the fans a gimick?

[chrisstankevitz]

Q: Why does one 150W MH light have a fan while the other does not?
http://www.marinedepot.com/IMD/aquarium_lighting_metal_halide_coralife_aqualight_advanced_hang-on_tank_mount.jpg http://www.nanotuners.com/images/viper2_sm.jpg

A: (Choose one)
a) One light is hotter than the other and needs a fan
b) The light without a fan is going to melt
c) The fan is a noisy gimick
d) other

[areze]

I could remove 3 of my case fans off my PC and it would still run fine.

just because it can tolerate the heat doesnt mean you want to go out of your way to not remove it.

not nescessary, but not a gimmick either.

might also get a breeze down to the water surface that would promote evaporation/cooling of the tank.