Powering 3 120mm fans

[phoenix777]

I believe 12v is good, but how much amp do I need?

 

[Paperdoc]

Depends on the fan spec's - check the maker's website. A quick look at several on Newegg (I used their links to the maker's sites) showed specs of 12 VDC, with current consumptions of 0.3 to 0.5+ amps. For three identical fans, just multiply by 3, so likely in the range from 1.0 to 1.6 amps total.