Any ideas on what could be making a random thumping sound in my computer?

[nine9s]

Any idea what could make a random thumping sound in my computer. It is a random noise which happens every now and then. It sounds like a thumping sound - as if someone was literally thumping the case, although more muffled (barely hear it while using my computer.) It is usually just one thump, and might go many minutes or even hours or not happen all day between thumps.

If I place my ear on my case, when I noticed it is happening, I can hear it better (it is a single thump - more a dull thud - every 20 to 30 seconds although it could go much longer between thumps or not have one at all even if I try to listen a few minutes - completely random, it is.) With my case side off, I cannot hear it over the fans but if I put my ear to the top of the case or other side of case, I can hear it again.

I thought a fan might be the problem but I checked all the fans and nothing is blocking any and I watch all of them - all three case fans, the CPU cooler fan and the 3 fans in my video cards - no problems from any - all are spinning well (fast spinning, no wobbling from any, etc.) If a bearing were going out on a fan, wouldn't the problem fan's spin be wobbly or uneven?

Any idea what the thumping could be?

My computer is fairly new (I put it together in mid May.) Here are any components of note:

Coolermaster HAF-XM case with two 200mm fans and one 140.
Asus P8Z77 Pro motherboard
Intel 3770K CPU
Zalman CNPS9900 NT CPU cooler
Gigabyte 680 OC video card
WD Cavair 640 HD
Samsung 830 256 GB SSD
Corsair AX750 power supply.

 

[rickon66]

Sounds mysterious, how about the case fans are pulling so much air out of the case that the sides are bowing in slightly from the vaccuum created then pop back in place when enough air leaks back into the case. Just a theory!

 

[nine9s]

Sounds mysterious, how about the case fans are pulling so much air out of the case that the sides are bowing in slightly from the vaccuum created then pop back in place when enough air leaks back into the case. Just a theory!

I could hear the thumping with ear to top of case with the side open.

 

[Ken g6]

Usually, fans make a rattle, not a thump. I wonder about your hard drive - if the heads were seeking too far off the drive they might make a thump. You might check the SMART diagnostics anyway. I'm used to checking them in Linux, but a quick Google finds http://hddscan.com/ for Windows.

 

[nine9s]

Usually, fans make a rattle, not a thump. I wonder about your hard drive - if the heads were seeking too far off the drive they might make a thump. You might check the SMART diagnostics anyway. I'm used to checking them in Linux, but a quick Google finds http://hddscan.com/ for Windows.

I have an SSD but do have a HD for data. I often hear the noise when I play a java based game that is saved to my HDD.

Is that program above safe to use? Does it do low level things that might cause system problems?

 

[Ken g6]

I really don't know about the above program, but a little more searching reminded me that certain HDD manufacturers make their own diagnostic software, which runs on Windows. Western Digital is among them. So I now suggest you try the software appropriate for your drive. Edit: Or here if it's really old.

 

[nine9s]

I really don't know about the above program, but a little more searching reminded me that certain HDD manufacturers make their own diagnostic software, which runs on Windows. Western Digital is among them. So I now suggest you try the software appropriate for your drive. Edit: Or here if it's really old.

Thanks, I am running the quick test now. After it finished it stated "Pass" but when I click on results, a small browser windows comes up with not able to display errors - like you get when go to off-line web site/down server.

 

[WiseUp216]

Just disconnect the hard drive and see if it stops.

 

[mikeymikec]

Occasionally, to prove whether the disk is making the sound I take the disk out of the case and connect it up so that I can put my ear to the top of it easily.

 

[AnonymouseUser]

Jammed optical drive trying to open/close?

 

[piasabird]

It is your hard drive having head crashes. You will start to cry later.
Fan is trying to eat a stray wire you should have put a zip tie on.
Your Power supply is thinking about taking a holiday.
Your system is overheating and your hard dirve is starting and stopping as the BIOS is shutting down your system intermittently till the processor cools off.
I have seen this happen when the Optical drive door gears will not engage. The door tries to open but it can not.

 

[piasabird]

Metal randomly flexing like in a heating and air duct.

 

[corkyg]

Also, consider a loose component or device that simply bangs in and out of place when used. It has to be something mechanical to produce a thump. Could even be a fan's sleeve bearing wearing out, and the fan thumps in and out of position. You can check that by push-pulling all fans, including the PSU fan.

 

[nine9s]

I have a guess.

Both of the 200mm fans have play in them toward air flow. For example, with my machine off, I pressed on the blades' center, of both fans, pushing in the direction that air would flow. There is play in both, and both make a thud like sound when I do this. if you press on the blades against the air flow, there is no play. I suspect that with air flow, randomly the blades get pushed with the air flow and then make the thud that I experience when I push on them in that direction. Probably heat, heavier air, etc. cause it to be random.

If this is the source and with both fans doing the same thing, therefore I assume their design to do this, I guess no problem.

 

[corkyg]

Depends on the type of bearing and how long they have been in use. Sleeve bearings are quieter, but they wear out faster. If they are a couple of years old, consider replacing them.

 

[JoeyP]

I had this exact problem. Turned out to be a fan bearing taking an occasional lateral load and thumping.

 

[nine9s]

All fans are new (mid May 2012.)

 

[sm625]

Unplug all your fans. Your zalman will keep your cpu cool enough as long as it is sitting idle. Does that make sound go away?

 

[JoeyP]

All fans are new (mid May 2012.)

Fans are mass produced and cheaply made. Plastic will never have the tight tolerances you'd get from machined metals. It may also be the fan inside your PSU, as it changes speed.

 

[nine9s]

It may also be the fan inside your PSU, as it changes speed.

It rarely comes on (it won't come on unless 40% load and/or reaches heat trigger per Corsair tech support.) I only consistently see it on when running high graphic games. When I hear the thumping, I have checked and the PSU fan is not running. I have watched the PSU fan and seen it come on (only stays on 10-20 seconds when it does) and heard nothing as far as thumping (nor the fan, is very silent.) Also, I had a game running and the PSU's fan stayed on, and I still heard nothing.

 

[mfenn]

Does the sound bother you? If so, your only recourse is to systematically isolate the fan (or fans) that's causing the noise and replace it. If not, there is no real harm other than that fan might only last 5 years instead of 10.

 

[JoeyP]

Another thing it might be is heat changing the sizes of materials at different rates. For example, as your motherboard warms, it expands. This might put just enough pressure on the standoffs to flex the frame slightly. One thing you could try would be to loosen the standoffs slightly.

 

[Slugbait]

If I were to hazard a guess, it sounds like The Chicken Heart that Ate New York City