4 pin Fan headers

[Izerous]

It is usually in the manual somewhere, small screenshot from my current motherboard. If not indicated at all I'd assume all of them are 1A only.

 

[KaptCrunch]

Standard high end MB fan headers are 1 amp and high output 3 amp for waterpumps. always not use the full 12 watts on 1amp IC controller use 10 watt load will live forever, high use 30 watt load.