Help determining which fan is making noise

[seanm1960]

I have 4 fans in my case. Rear 120 fan, smaller front fan, CPU fan and PSU fan. Vid card has no fan. One of them has starting making noise the other day, and I would like to determine which. What I would like to do, is take the computer out of my bedroom, and put it on my kitchen table with the side off, and try to narrow it down that way. But the noise only happens when the computer has been on for a while, and I cant seem to get a grip on how long it takes.

The other thing I was thinking is to use process of elimination and just replace each fan one by one, but that could take a while, and be costly. Is there a better way to go about this? Thanks.

 

[Darkbreeze]

What kind of noise is it? Is it a vibration or is it bearing noise? If it takes a while to start it's probably bearing noise. Just go through running it with one of the fans unplugged, then another, etc., until you figure out it's not making noise anymore. It's not going to hurt to have one fan unplugged, especially if you have the side panel off. Obviously, don't unplug them while it's running. Just unplug one of them, run it until it either starts again or you're sure it's not going to, and then move on.

If it's a vibration, you can add rubber pads to the corners of the fans to elimate the transfer of vibration to the case. If it's the CPU fan, clearly you'll know it if none of the other fans caused the noise to stop. Don't rule out the PSU either. That's the most common fan to fail due to bearing fatigue because of the heat inside the PSU.

 

[seanm1960]

Doesn't seem like vibration - it's a constant whirring noise at a fixed pitch. Does that sound like it would be bearing noise?

How would I go about unplugging the PSU fan?

 

[Darkbreeze]

Does your case have air filters in front of the fans? It almost sounds like one of the filters has pulled free and might be lightly slapping the fan blades. Otherwise, it's probably a bearing. You can't unplug the PSU fan. Thing is though, since it doesn't do it until the unit gets nice and warm, that lends credibility to it being the PSU since many models don't kick the fan in until it gets to a certain temperature while all the other fans run, at varying RPMs, from the time you turn the unit on. Just stick your head down by the PSU when the noise starts. It should be fairly apparent if it's coming from there. Otherwise, eliminate all the other possibilities until that's all that's left.

 

[seanm1960]

Not sure about the air filters... will check. Thanks!

 

[Darkbreeze]

No problem. FYI, they are just very thin, so it may require looking closely.

 

[seanm1960]

Ok, so I think I have narrowed it down to the CPU fan. I got the case open, and it actually didn't take that long for the noise to start. When I put my thumb on the very center of the fan and press lightly, the noise goes away. I checked the MB standoffs, and they are all as tight as can be. So, should I go for another CPU fan?

 

[Darkbreeze]

Make sure it's securely fastened first. It could be that the noise actually IS vibration. Make sure the heatsink is fully seated, don't remove it or you'll have to re-paste. Make sure the fan is fully attached to the heatsink. Is it a stock CPU cooler? If so I'd probably replace it. What are your system specs and is anything overclocked?

http://www.tomshardware.com/faq/id-2299418/obtain-basic-advanced-system-information.html

 

[seanm1960]

yes, the heatsink is seated poroperly, and the fan appears to be in place. It is the stock cooler/heatsink.

I have a core i7 4820k 3.7 Intel chip.

Thanks again.

 

[Darkbreeze]

Does that have liquid cooling?

 

[seanm1960]

No liquid cooling - everything is stock.

 

[Darkbreeze]

Was that a pre-built system, because that CPU does not apparently come with a stock cooling solution, so it's likely a cheap cooler was installed by the OEM or vendor if it was, in which case it's not surprising the bearing has failed if that's what has happened. Any idea what you can budget for a cooler?

I'll be happy to recommend a replacement. Since you're not overclocking and it doesn't sound like you're likely to do so, a good budget cooler should be much better than what was on there. Probably something like this:

PCPartPicker part list / Price breakdown by merchant

CPU Cooler: Scythe BIG Shuriken 2 Rev. B 45.5 CFM Sleeve Bearing CPU Cooler ($33.62 @ NCIX US)
Total: $33.62
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2014-11-23 22:33 EST-0500

 

[seanm1960]

Right - it doesn't come with a cooler, but I say it's stock, bc its the Intel cooler that goes with it:

http://www.newegg.com/Product/Product.aspx?Item=N82E16835203013

I am not really into all of the big, jumbo aftermarket coolers - I have tried a few and I can never seem to get them onto the MB right. Maybe I will just get another Intel one again. Thanks.

 

[Darkbreeze]

Yeah, that cooler is fine too. The Scythe Big Shuriken is not a tower style cooler, it's a top down cooler, or downdraft if your prefer, just like the stock version, but it does require using a different hold down bracket and offers significant cooling performance over the stock unit. The stock unit will work fine though for any cpu not overclocked, like yours.