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Why does my computer make a grinding noise when starting up?


Recently, my computer has been making a very loud grinding noise when I boot from cold. It seems to take forever to stop and everything goes very slow during this time. What is this and how can I correct whatever is wrong?

There are two possibilities that come to mind. One is something that you should deal with, but it’s nothing to really panic over.

The other is definitely worth panicking about. And in fact, given that your machine is running slowly while this is happening, it might be time to start panicking right now.

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Problem #1: Fan issues

The problem that you want is a fan issue.

Many computers will run all the fans at full speed for a few seconds. They do this at start up to make sure that the fans work and to dislodge any dust or dirt that may have accumulated that a low speed wouldn’t just blow out of the way. If there is something partially obstructing the fan, the blades could be hitting it and that could easily sound like a grinding noise.

It’s fairly easy to fix if you open up the computer and look for things that are bumping into the blades.

This has happened to me multiple times. The most recent was when I installed a hard drive. I rerouted the cable to make room for the hard drive and as a result, the cable ended up sitting in front of the fan. I heard it and I fixed it simply by moving the cable out of the way.

Problem #2: Internal destruction

The other option that concerns me is the hard drive.

Your Disk is on Fire!First, back up!

If your machine is working and you’re not already backed up, stop reading right now and back up that machine. Your data may be at a serious risk of complete, irrecoverable loss.

Sometimes, when a hard drive is failing or about to fail, it can make those kinds of grinding noises. It’s a precursor to something much, much worse. Internal destruction is usually what’s next.

That grinding noise is something loose inside the hard drive, where there simply shouldn’t be anything loose. That typically means that when that thing becomes completely loose, it’s going to go flying around in there and cause all sorts of destruction within the drive itself.

And that kind of destruction is typically irrecoverable.

That’s why I started by saying back up, now, while it’s still working.

Backing up really is the first step of what turns out to be the only real solution. You’ll first back up, then replace the drive, and restore all of your data to it from that backup.

How do you tell which it is?

My approach would be to open the box and just listen carefully to from where the sound is coming. It’s usually pretty clear – it’ll probably be coming from one of the fans or from one of the drives.

Like I said, the fact that you’re experiencing severe system slowness while this noise is happening really has me concerned about the hard drive. That’s probably what you want to be looking at first.

Right after you back up, of course!

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30 comments on “Why does my computer make a grinding noise when starting up?”

  1. If it is hard to figure out where the sound is coming from – use something solid, like a hammer handle (or something longer), and place it on different parts of the computer and put your ear up to the other end. Sound travels through solids a lot clearer than air. You can zero in on what is vibrating pretty fast. Learned it from my Dad when he was working on the family car, but also works great on computers. If you are getting old like me and it is uncomfortable to put your head down into your computer, this is a good second option.

  2. Fans (especially cheaper ones) that are starting to wear out often start up cold with a wobble that can make a peculiar sound that could be described as grinding. They will eventually settle into smooth rotation after a few seconds/minutes (often faster with a gentle tap). If this is the case then it’s just a simple matter of replacing the fan. Simple assuming the fan is not proprietary in connector, size or mounting.

  3. Opening up a laptop to access the fan sometimes results in taking the whole thing apart.
    Same for replacing the CMOS battery.
    Not an easy job in the first place.
    But if a fan makes a grinding noise it’s almost always the bearings that are gone.

  4. Hi, Leo,
    Just wanted to tell you that your newsletters/advice/observations etc. are still very valuable and appreciated. I hope you never “retire” from publishing “Ask Leo” and the other great newsletters and advice. I get about 70% of my computer information, understanding and guidance from your postings. (No reply necessary.)
    Best regards,

  5. my computer also makes a gridding noise.The reaaon is that you have plugged out the connections.The solution is very easy.Press f8 or f10 or f12 or del.This will open enter setup.Then go on bios settings.Then go to all errors and then select no error.Then press f10.And then click yes.Then restart.

  6. I am a luddite mostly…very little electronics knowledge.
    My PC was making noises on cold start up, like a fan vibrating. It was loud. The PC would freeze within a couple of minutes too. I’d just press reset because ctrl/alt/del didn’t work. Anyway, this was progressing to repeat itself 4-5 times before the PC would start working.
    I pulled the cover and vacuumed loads of dust from the box, mostly from around the fan. Upon restart, it worked much better, but the fan still occasionally makes the same rough noise.
    I’m guessing the fan needs to be changed. It is an eight year old system so probably overdue.

    • I do seem to have this issue when my computer is turning on and when it is cold. If it is a cold day or I hit the computer it will start making that sound but after a few force shutdowns it will boot up and chug along. It is a 4 year old computer with a hard drive but I think the fan is the issue as that is always blowing at full blast. Still runs fine and kinda speedy. Just turn it off and back on again a few times and see if that fixes the issue.


    • I’ve been having a similar issue, Judy, and the conclusion I’ve come to in my case about the noise is that my computer room is getting too cold at night and I’m starting my computer before the room warms up in the morning. The thermal shrinking seems to be causing the fan to grind against its housing. Once my computer boots fully and displays its temperature monitor, it’s at around 10C. If you keep your computer in a room that goes below about 45F/7C I’d think a similar issue is likely. See if there’s a way for you to check what your fan is grinding against, though, as it might be a wire or something rather than the housing.
      However, grinding noises can be just about anything; if yours is a desktop PC, I’d recommend opening the side of the case to find the source of the grinding. If it’s the fan, find out what it’s grinding on and try to move things out of the way if necessary. If it’s the hard drive, do as Leo suggests and back everything up.

      IF your computer is a laptop, I wouldn’t recommend taking it apart. I’d say go to a PC repair place and let them know the issue and the conditions your laptop have been kept in (like if the room gets really cold).

      • Amias, I, too, have this problem…When my computer room is cold, and I start up my computer, it makes a grinding noise. I listen carefully to where the noise is coming from, it’s coming from the power supply area. As soon as the computer room warms up, the noise is gone. But as soon as there is a drop in tempature the computer will grind again..its a 5 year old Sony Vaio and it has already been worked on, meaning, everything in it has been replace except for the power supply. Other than the grinding the “old girl” has been working quite well.

  8. Describe your thread i can see how old this thread is, and also have similar discussions to my current problem. i need help. my toshiba satellite makes a strange fast-gearing noise upon booting for about 2 seconds before opreating normally. the strange noise started less than a week now. can i get help now??

  9. Thanks l read most comments and picked something, otherwise mine is a bit different when I start my computer it makes a very loud noise near the processor and it doesn’t diplay anything on the monitor,what could be the problem and how can I fix it?

  10. Well my PC is suddenly acting weird , on just few of the Boots , the boot is extremely slow and the case fans are Loud as hell , so after the boot happened , i checked CPU ID Monitor , and cpu temps , hdd temps , hdd utilization , ram utilization (different app) , cpu utilization all were low , but the pc was slow as hell .
    I shut down and restarted it , then the next boot , was rather normal , no loud fan noises , just a regular boot , which was fast , just as it normally is around 17-20 seconds.Now , my problem is that this happens every 2-3 boots , this problem of loud fan and slow boot , i just need to restart or shut it down from mains , until i get the standard boot.

  11. It takes my computer about 2 to 3 minutes of sitting and humming before it catches and stats up….it just started that about 3 weeks ago for no reason, fan works fine, have a 1tig hard drive had all info put on it by computer guy..I am wondering could it be something from the start up files? surely nothing inside has gone bad…..I have Windows 10, but I use Chrome and Firefox as my browsers and for my games on FB.I noticed when the noise started only 1 game had a slow down and freeze…

  12. Hi
    I don’t understand why there is a grindong sound in my dell desktop. Its in hard ware but I don’t understand where exactly it is.
    Does it have any other issue which you have not talk about above?

    Websites also get many advertisement. What is the best free cleaner I should download to save computer from annoying advertisements?

    • That article covers everything we have on the subject.
      We don’t have any recommendations for ad-blockers.

  13. My computer is making a scratching noise and it hasnt for 4 days now, but all of a sudden it started and i am very terrified about the hard drive thing. I have animations on here i am working on and do not want to loose it, and my aunt said she would NOT buy me a new macbook. I asked my fellow friends on a flash game forum and they said its the fan and it happens to them all the time, but let me just explain the noise:

    It sounds like metal is being scratched, or it COULD be my imagination and just be the fan, although i am not very sure. I have never dropped my computer though i have banged it a few times, the recent being about 6 weeks ago, and it didnt bang hard and everything was fine. I really need to know, Can they fix the drive if it is loose or is it impossible to?

    • It could be either the fan or the hard drive. But always prepare for the worst.

      A drive normally can’t be repaired, but it is relatively inexpensive to replace. But you should immediately back up everything. If you have an external hard drive, copy all of you important files to that and then do a system image backup so you will be able to restore the image to your new drive. Macs have the pre-installed Time Machine for that.

      If you only have (a) flash drive(s), you can at least back up your important data. A USB or SD flash drive isn’t the best backup device, but if it’s all you have, you can copy everything that fits onto it.

      Then if you don’t have an external hard drive, get one and take a system image backup. Start taking daily image backups starting with a system image and continuing with daily incremental backups. You can use it restore your system to your replacement drive. Then after replacing the drive, continue with the backup plan.

  14. So after reading all of this nothing addressed the cause for a laptop making a grinding sound for a laptop with no moving parts. I have a xps13 it does have fan but has never been on when the sound has occured??? The laptop is a year old and has only made the noise 3x now. It has no other issues and nothing in diagnostic test shows me a problem. The sound is not pretty and I just need to pin point what the heck it is. Please anyone that can help or explain to me how a fan that is not running or a ssd is suddenly trying to spin. It just did it again only for a sec oh and I have checked the temp to make sure fan is not trying to come on but cant it has not reached the temp required for fan to start

    • Every time — literally every time — I’ve had this happen, and others I know of have had this happen, it’s a fan. (Typically a fan bearing.) You may have more fans internally than you’re aware of. Not sure how you’re determining that the fan isn’t running, but often the problem generating the noise also prevents the fan from running, so you might not feel any moving air.


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