CPU fan stuck at full

[psy-q]

I just got my G750JW-DB71 on Thursday. The CPU fan has been running full speed every second the machine is running. AC, battery, it's all the same.

Anyone heard of this before and know a fix. I upgraded from 207 to 208 BIOS with no change.

[villiansv]

What is the temperature? Use HWMonitor.

[psy-q]

Temperature holds at 29-30C at 3.4GHz idle. Pretty cool for an i7 so I assume the cooling system is working correctly, just more then it needs too.

[hmscott]

psy-q wrote:
Temperature holds at 29-30C at 3.4GHz idle. Pretty cool for an i7 so I assume the cooling system is working correctly, just more then it needs too.

psy-q, with a CPU temp that low, there isn't likely a background process taking up 100% CPU - the CPU temp would be much higher. You can still check for a stuck process causing the CPU to heat up, maybe not 100%, but high enough to trip the fan on all the time.

It could be a hardware issue causing the fan to run full all the time. You could try to boot on a USB Linux and take Windows completely out of the picture - if the fan stops while Linux is running it probably is the Windows install and you can reload that from the recovery partition.

You could also go into the BIOS and see if the CPU Fan is still running Full while in the BIOS. If the CPU fan is still running Full while in the BIOS then you can also rule out Windows as the problem.

Please come back and let us know what you find as the problem.

[villiansv]

Indeed, that's really cool. I'm idling @40C in a reasonably cool room, fans blowing full speed may be responsible for the 30 you are seeing. Sounds like a fan controller issue, but as there are no controls for the fans it's hard to do much about it. Try unplugging from power, taking the battery out, keeping the laptop like that for a few hours (overnight). Maybe reset the BIOS settings, upgrade to the latest BIOS version if you haven't. Other than that, it sounds like you'll have to RMA.

P.S. If you boot windows in safe mode, do you still get the same fully blowing fans? Maybe try a live linux distro, so you can at least rule out software reasons (though I think fans are BIOS-controlled, so it's unlikely).

edit: heh, hmscott beat me to it 🙂

[hmscott]

villiansv wrote:
...
edit: heh, hmscott beat me to it 🙂

Great minds think alike 😉

villiansv's suggestion to select defaults in the BIOS to see if that will reset the FAN controller is a good idea.

IDK if the unplugging/removing battery trick will work, as the CMOS battery is still in play - I think we have to remove the top keyboard plate to get at the CMOS battery, so that isn't going to be easy - and voids the warranty. But, unplugging / removing the battery overnight is still worth trying - better than boxing it all up again and shipping to Asus.

It also might be worth looking to see if there is an Asus authorized repair depot within driving distance.

The single time I have had to go in for repair years ago I was able to drive over (about 20 miles) and patiently wait for support - I had to drive back again as they debugged the problem to a bad video card and needed me to come back when they could get one in stock. Still faster/better than being without my laptop for weeks - they let me go home the first day with the laptop as the video card was only flaky under load.

[villiansv]

hmscott wrote:
IDK if the unplugging/removing battery trick will work, as the CMOS battery is still in play - I think we have to remove the top keyboard plate to get at the CMOS battery, so that isn't going to be easy - and voids the warranty.

It does void the warranty, but it's not as hard as you'd think. I posted a guide a couple of days ago that details the process of modding the backlight color of the keyboard, and you can use that to see what you need to do to remove the keyboard panel - linky

[hmscott]

villiansv wrote:
It does void the warranty, but it's not as hard as you'd think. I posted a guide a couple of days ago that details the process of modding the backlight color of the keyboard, and you can use that to see what you need to do to remove the keyboard panel - linky

Thanks villansv, bumped that thread, it should be sticky.

Love that photo of all those screws in position on the table top 🙂

[BlackHawk]

This is actually pretty cool. I would like to know how to force my cpu fan to run at full lol. Seems he stumbled upon it by accident.