Motherboard fan control header -- can I use a Y-splitter?

KenAF · Post by **KenAF** » Wed Feb 13, 2008 12:45 pm

I recently purchased a new Gigabyte DS3R motherboard.

Like all recent Gigabyte motherboards, the DS3R has bios fan control for the CPU header. While the CPU is below a temperature, it will reduce the fan header voltage to reduce the speed (and noise) of the CPU fan.

My question:

Can I use a Y-splitter cable to connect a CPU fan and case fan to that same fan header? If yes, is there any danger in doing so?

psiu · Post by **psiu** » Wed Feb 13, 2008 2:18 pm

You could overload the plug--it will be drawing twice the current.

KenAF · Post by **KenAF** » Wed Feb 13, 2008 2:41 pm

psiu wrote:You could overload the plug--it will be drawing twice the current.

Is that likely to occur with two low-rpm 120mm fans? Say, 2x Scythe S-FLEX SFF21E?

VanWaGuy · Post by **VanWaGuy** » Wed Feb 13, 2008 2:49 pm

My bigger concern would be what is the combined speed signal going to look like, and is the fan going to be controlled in a reasonable manner?

smfiou · Post by **smfiou** » Wed Feb 13, 2008 3:50 pm

that is what i did to control my 120 mm noctua case fan and 80mm panaflo cpu fan. so now on heavy load, both fan turns faster :D been running like this for a year.. doesn't seem to be any problem. only the cpu fan header seems to be controlled by asus Q-fan. running a8n5x. by the noise, both fan are clearly going to 12 volts on heavy load.

Lawrence Lee · Post by **Lawrence Lee** » Wed Feb 13, 2008 5:18 pm

I burned out a fan header doing this with a Gigabyte DS3. The same thing with a DFI Ultra-D. They were two low power fans too (1.8W a piece). Can't say I recommend it.

KenAF · Post by **KenAF** » Wed Feb 13, 2008 5:24 pm

Lawrence Lee wrote:I burned out a fan header doing this with a Gigabyte DS3. The same thing with a DFI Ultra-D. They were two low power fans too (1.8W a piece). Can't say I recommend it.

Thanks for the warning. I guess I'll use separate fan headers.