At wits end. Need help [SOLVED]

So in May 2014 I effectively bought a new PC in the form of a motherboard bundle. In July 2015 I got a new case replacing an old case that had been home to the guts of two PCs before its last incarnation with the new motherboard bundle.

Ever since I have been experiencing a fan issue that of late has been happening more and more often. It used to happen a few times after boot and settle down but now the issue happens every couple of minutes and it driving me spare.

The issue is some or all of the fans will spin up to 100% for about 5-15 seconds and then go back to normal operation.

I thought this was because the five fans (140mm x2 120mm x3) did not have the fourth PWM pin.

The CPU is taken care of by a hydro cooler.

So today I took delivery of five replacement fans. 120mm & 140mm

Indeed they are noticeably quieter. But the problem is still happening!

The motherboard is an ASUS P9X79 LE

I dual boot between Linux and Windows. Issue happens in both operating systems.

Hydro cooler is a Corsair H80 My CPU block looks a little different from this picture. The unit has a wire to supply power coming from the block but not the radiator. So I have nothing attached to my CPU OPT header on the motherboard. The radiator is attached to one of the 120mm fans.

Motherboard BIOS is at the highest and last version. I have tried setting all the fan speeds to manual and the issue still happens.

Here is the sound

Here is my hardware

Any suggestions on what to try next?

Does it happen with only one fan plugged in?

I admit I have not tried that yet. I will give it a go tomorrow. I confess I am too annoyed to take my PC apart again tonight.

I will try disconnecting the fans one at a time and see if it makes any difference.

Could always get a bunch of 3 pin to molex adapters and just power them all right from the PSU, or a fan controller,

The Sentry Mix 2 is pretty alright for the money

Fan controller was my next thought as well. I don't trust the motherboard fan control anymore. Indeed this motherboard has been a bit of a disappointment...

Streetguru, my case has a door that closes over the 5.25 inch bays, so clearance for the controls is a major issue. I have maybe 6mm of clearance. Do you have one of these controllers? Will it be enough space?

The unit you link goods like a good candidate.

You could always just recess the controller in your bay a fair amount if clearance is an issue, but I can't imagine the sliders are very long.

Yeah, with the door closed it won't be too offensive. Means I can ramp up the fan on the CPU radiator easily as well...

So it needs two spare molex.

Just gonna open the case and double check....


Okay, spare sockets in the PSU are present and a dive into the bag'o cables presents the suitable braided molex cables / connectors.

Unit has been ordered for delivery on Monday or Tuesday...

I will update the thread then.

Thank you for your assistance!


So, still waiting on the fan controller but this was pissing me off so much in the meantime I just decided to direct power all the fans off a five way splitter connected to a molex.

So now all the fans are running 100%. Hydro cooler still connected to the motherboard. But something is still spinning up and down. The GPU as it turns out. I have taken it out and blown all the crap out of the heat sink fins with a can of air. Put it back in a different slot so the airflow is different but still the same.

So for whatever reason the GPU fans were spinning up and then all the case fans joined them in sympathy. Can the GPU send a command to the case fans saying "Help! Please run faster I think I am hot" ?

The card is getting on a bit now so unless I can find some kind of software update for it I guess it is headed for the bin. I had hoped to wait until the NVIDIA 1000 series cards came out...

Sorry for not replying sooner. Yes the guilty party was the GPU that was somehow causing the case fans to spin up as well. You can hear it in the sound I linked. The GPU fans turn on first and then the case fans a few seconds later.

The "old" GPU, a GTX 770 is still in warranty and has been RMA'ed. If it behaves in the same way when tested at the resellers I will hopefully be reimbursed which covers the cost of the GTX 970 I bough to replace it.

Now the rig is nice and quiet and I am happy with the fan control unit recommended by Streetguru in this thread.

Will mark as SOLVED.