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Weird fan problem - ROG GL702ZC fans running full blast all the time - help needed!

Level 7
Hi folks,

Just wondering if there's anyone out there who can possibly help me out with this fan problem I'm having.

I've had my GL702ZC laptop for about 3 years now and in that time it's been really dependable and virtually problem free. This fan issue however has been happening for several weeks now. Within seconds after the Windows login screen the laptop fans go straight into top speed, producing a very, very loud noise that is simply impossible to tolerate for more than a few minutes. The weird thing is that the air coming out is completely cool so it doesn't seem to be a temperature related issue - it's happening even in an idle state with no programs or major processes running.

I've searched different forums online and it appears that indeed others have had this exact same problem with this laptop model. I have tried some of the possible workarounds that have been suggested- updating the BIOS (two of the most recent versions provided on the ASUS support site) uninstalling and reinstalling the graphics card driver and adjusting the battery power settings, but to no avail. I have opened up the back to inspect the fans/battery for any loose connections yet everything seems in order and there is nothing noticeably amiss. I tried a clean install of Windows 10 and had no luck with that either. Other users have reported that since the excessive CPU fan speed is showing up in the BIOS (at over 6000 rpm by the way) then this could be a problem outside of Windows.

Something of interest was mentioned in the post below, where the user experienced a small power surge at their home created by a toaster.

They claimed that the problem with the laptop did not arise until many hours after this, so thought it was unrelated. I don't know if it is a complete coincidence or not, but the day that this problem occurred I also experienced a very brief power cut that lasted literally a couple of seconds, with the laptop fan issue beginning to occur within minutes of this happening. However, I'm not convinced that this was the cause either. I do remember two different occasions several months ago when the laptop would not wake up from sleep mode and the fans did get really loud, just like now - I could not log back into the system and just had to forcibly turn the machine off with the power button. Things did return to normal again after powering on and off again but I guess it's possible that the fan problem was brewing even back then.

I logged a support ticket with Asus but they just recommended to update the BIOS, which I have already tried (and told them that I did in the email), and it didn't work. The alternative, sending it to the nearest Asus support depot (which is outside my country) is not viable - the machine is long since out of warranty and so with the combined cost of freight and repairs, it would probably cost more than it's worth!

I am considering replacing the fans with new ones - although they're doesn't seem to be a problem with their functionality, maybe there is a dodgy wire that is not communicating with the motherboard or thermal sensor or something. However, I'd like to know if someone else has had any success with this before potentially buying new fans for no reason.

If that doesn't work I'm at my wits end with this!

Any help or comments would be appreciated


Customer Service Agent
Thank you for posting .
May I know serial number of laptop that you could share me with private message ?
I can look into the RMA story or contact history.
Usually fan control error may be caused by BIOS or System. That's why updating BIOS will be first step.
Before you replace fan module, I will suggest thermal paste will be first priority to replace.