Motherboard Fan Power Ratings?

[Essence_of_War]

How does one figure out how much power their motherboard fan headers can supply?

I have an AsRock z77 Pro4 in a carbide 500R. I was planning on switching/upgrading some of the fans, which are currently connected to the carbide 500R's fan controller, and I was planning on connecting the new fans to my motherboard fan headers, possibly with 1-2 3-pin Y splitters in the mix.

 

[Ketchup]

I don't have the exact number you are looking for on hand, but I have split 2 120's on single motherboard fan headers before, and haven't had any issues. Get over two, and you really want a fan controller.

 

[Golgatha]

Anything over 1A and you should probably think about using a fan controller directly attached to the power supply.

 

[Essence_of_War]

Anything over 1A

Shouldn't be anywhere close to that. Each fan should be < 1W.

I'm looking at driving a total of 2x120mm and 2x 140mm fans off of 2 3-pin headers. Each fan should be < 1W, and 1A @ 12V -> 12 W.

 

[crashtech]

I thought the z77 Pro4 had plenty of fan headers, what's the deal, are some of them not controlled by the BIOS?

 

[boondocks]

When I'm not water cooling a particular build, I contact the manufacturer and ask them outright what the fan headers are rated at.
For the last several years the mainstream Gigabyte boards generally have headers rated at 1A.

 

[Compman55]

Back in the day the rule of thumb is 2 per header. These specs are super hard if not impossible to locate. Often the manufacture will give a generic response.