H55M UD2H Sys Fan v low rpm?

[marktomlinson90]

Hi everyone,

Just a quick question about my new build, centred around the h55m ud2h (bios f10).
Basically, the system fan 4 pin connector is not spinning the fan sufficiently. It stays at approx 500rpm. I have plugged it into the cpu fan connector however and it revs up to regular high speed.

I am using a Corsair H50 cooler, and when the pump is plugged into the system fan connector instead of the cpu fan connector, the cpu reaches 80 C within half a minute, as the pump (which is supposed to work at around 1400rpm) is clearly receiving a third of what it needs.
I guess this is quite a common issue with Gigabyte boards judging by Google searches, but I can't find any clear explanation.

I plugged the fan into an Asus Chassis Fan connector to check and there was no problem. The Gigabyte Bios offers no options whatsoever with regard to controlling system fan speeds. With only two fan headers on the whole mobo and one taken up for the Corsair H50 I haven't got many options, and am not best pleased to be honest!
Any help on this issue would be greatly appreciated; it's the one thing stopping me from screwing the side panels back on my new build for good.
Thanks very much.

Mark

[Dark Mantis]

Hi and welcome to the forum Mark.
I have heard others on the forum complaning of a similar thing but as far as I am aware it was because of BIOS issues. Depending on the currewnt draw you could always use a splitter to give you more fan options or as with the bigger fans nowadays use a takeoff from a molex connection. If anything I would have expected the Gigabyte boards to be better able to supply the current needed because of the double thickness copper layer.

[1Day]

Have you made any adjustments to the settings in the bios with respect to fan management? Or better still have you tried to load the GIGABYTE Dynamic Energy Saver software that comes with the motherboard which allows you to control the fan speeds from the OS?

[marktomlinson90]

Wow, thanks for the quick replies guys. I'll install this dynamic energy saver program and get back to you. I was thinking of just using another cable - could you possible direct me to the correct one please? It's a 4 pin fan so i'm not having much luck finding 4 pin system fan to molex connectors.
Cheers,
Mark

[Dark Mantis]

I think a while ago someone else was looking for the same thing and if I remember correctly there were several different types on Amazon. I suggest a search on there.

[marktomlinson90]

Right, does it really matter if I stick the 4 pin fan onto a 3 pin connector?

As for DES, i've just installed it and get a 'Smart Fan Initial Failure' message. I have no idea what the deal is (it may be because CPU Smart Fan Control is disabled in the Bios) but i'm looking for a way of changing the system fan speed not the cpu.

The program looks good but nothing is really clickable (such as the vga, hdd etc pics under Power Saving Status). I've spend way too long on this rig today to bother about trying to figure this out - there are no tips when a mouse is hovered over.

I'm surprised Gigabyte haven't fixed this pretty simple issue, Asus don't have this problem, but I think i'll go with the splitter and save the headache.
Thanks!

[Dark Mantis]

Yes I am not a great lover of these free programs that all motherboard companies like to include with their boards. Even the ones that don't mess up your system don't usually work very well.
Just had a quick look on Amazon for you and came up with this although I am sure there is a lot more on there.

http://www.amazon.co.uk/NesteQ-Molex-Supply-Splitter-NSK-1205/dp/B003JBCQKY/ref=sr_1_5?s=computers&ie=UTF8&qid=1284590612&sr=1-5

[1Day]

Sorry to hear that - I did a quick test this morning with the H55N board and using a three pin connector I had no issues at all. I wonder if the 4 pin connector that you are using is causing this - I can only assume that the extra pin is for the controller to set speed of the fan. All the four pin fans that I have do have some form of speed control. Did the fan come with a controller?

[Dark Mantis]

Sorry to hear that - I did a quick test this morning with the H55N board and using a three pin connector I had no issues at all. I wonder if the 4 pin connector that you are using is causing this - I can only assume that the extra pin is for the controller to set speed of the fan. All the four pin fans that I have do have some form of speed control. Did the fan come with a controller?

I think that you will find that the speed is controlled by the BIOS via the forth pin.

[1Day]

Sorry to hear that - I did a quick test this morning with the H55N board and using a three pin connector I had no issues at all. I wonder if the 4 pin connector that you are using is causing this - I can only assume that the extra pin is for the controller to set speed of the fan. All the four pin fans that I have do have some form of speed control. Did the fan come with a controller?

I think that you will find that the speed is controlled by the BIOS via the forth pin.

Thanks for confirming that. Much appreciated. 

[marktomlinson90]

Yeh, i've done a bit of searching and the 4th pin is just for bios fan control, it doesn't supply any more power. Nope it's just the Corsair fan that came with the H50, no control. Will get the splitter - thanks a mill for your help you guys.
Mark

[1Day]

Right I went and pulled a 4 pin fan from the store room. Stuck it on the test bench and this is what I found.

It will not run at full speed on the 4 pin header with out prompting. Prompting means an instruction from the bios to run at max and ignore the temp of the bit of motherboard it is mean to be looking after. That is a bit weird in my view but there you have it. I took a hair-dryer and heated up the south bridge and it spun up to max after a few minutes of that treatment. Took away the heat source and rebooted, spun up and then stopped.

But will run at 100% if put in this configuration on a three pin fan header.

[Dark Mantis]

Right I went and pulled a 4 pin fan from the store room. Stuck it on the test bench and this is what I found.

Ok so now I am really envious! You have a storeroom, I only have a store cupboard

Anyway at least we know for sure now, and in future can explain how to get around it. What would you women do without your hairdryers eh? 

[absic]

I only have a store drawer! 

[Dark Mantis]

Not like you absic, you are normally boasting about the size of your stuff!