All computers are bound to make some noise, but rattling and grinding noises are not among the ones you should be hearing. With how many components computers have, it can sometimes be difficult to narrow down what's causing the noise and what to do about it. Here are three common causes of these sounds and how they can be fixed.
Your computer generates a lot of heat, so to effectively get rid of that heat and keep cool air moving into your computer tower, several fans are necessary. Your graphics card likely has a fan, as does your processor. Your power supply has another, and there is often at least one fan in the case itself to push air through. A rattling or grinding sound can sometimes be due to one of your fans no longer working smoothly.
There are several ways this problem can manifest. The first is that the fan bearings may simply be old and dry and need lubrication. The second is if anything is touching any of the fans, such as a stray cable. You can help avoid this problem by making sure all of the cables are secured to the case and that no loose ends are left dangling.
The third is that the fan is old and off-balance. In this case, the fan will need to be replaced, but the good news is that most case fans are very inexpensive relative to the rest of the computer and can be easily swapped out.
If you're having trouble narrowing down which fan is causing the problem and feel up to troubleshooting, disconnect each fan from the motherboard one by one until the noise stops.
Loose Case Siding
In some instances, the case itself may be causing the rattling or vibrating sound. This can happen if one of the side panels starts coming loose, if one or more screws in the case are no longer tight, or if you're missing a rubber stand or washer. The movement of your computer parts can cause the metal to rattle against metal and cause a constant sound that's difficult to locate.
There are a few ways to troubleshoot this problem. If you're able, remove the side of the case, and see if the rattling stops. If so, the siding may be warped or loose, or you may simply need new screws that offer a tighter fit.
You can also keep the case open and see if you can see or feel the source of any vibrating on the inside, such as where screws hold your hard and optical drives in place. Also, check any metal case coverings that block ports and openings that aren't used by your motherboard, as these can sometimes come loose and start rattling.
If the problem isn't easily remedied, you can always have your computer's components moved over to a new case. If you hire a professional to do this for you, they can also make sure all your cables are secured and everything is arranged to optimize airflow and cut down on noise.
Hard Drive Failure
Unfortunately, grinding sounds can also be caused by a hard drive failing or beginning to fail. Specifically, this will happen with hard disk drives, or HDDs, that use moving parts to store and retrieve data. These are still more common and have greater storage space than solid-state drives, but their use of moving parts means that physical wear and tear on the drive can cause it to stop working.
Even if you aren't sure if this sound is coming from your hard drive, immediately back up whatever data and files you can. Alternatively, if you don't feel comfortable turning your computer on, a computer repair service can help retrieve the data for you even if the hard drive isn't working perfectly. This should be done sooner rather than later, however, as it becomes progressively harder to retrieve data from a hard drive the more damaged it is.