Loud fan grinding noise

[Iggy Wolf]

I recently upgraded to a new Toshiba HDD 3 TB. However, I don't think the noise is coming from the HDD, since the HDD makes a regular normal disk noise separately of the fan.

Problem is, I don't know which fan is making the noise. To make matters more complicated, it doesn't happen all the time, and pretty much is silent upon restart and all other circumstances.

The only 2 times that it has happened so far, have been after I've had the PC on for the entire day, at which point by the time 3 or 4 AM comes around, the noise starts and yesterday it did not stop unlike last time until I turned the PC off.

I'm not sure whether it's a failing fan, whether the CPU, PSU, or case fan. In any case, how would I find out which one it is, and which of the fans is most likely to be making that loud grinding noise, winding up and down periodically?

[Big Boom Boom]

In bios, make each of the fan run at full speed and see if you can identify which one. If not, then it's either PSU or GPU. To check GPU can use one of the many software to control GPU fan and ramp it up.

[Iggy Wolf]

I actually have a program that already comes with the GPU (GTX 970) ASUS STRIX monitor. I checked whether it was the GPU fan but the fan showed it only spinning at 10%. The computer was idle. Hell, right now it's at 0% since nothing is happening to heat the card. I had a PSU fan fail on me once, but I knew it was happening because it was consistent and was ALWAYS making a clanking noise on my old PC, the kind of sound that indicates that it's dying and/or constantly slowing down and restarting. I just hope it's not the CPU fan. (Might be if the PC being on the entire day managed to heat the CPU fan sink hot enough).

[Big Boom Boom]

Make each of the fan run full speed and listen to their noise. It's not hard. The only one you can't control is the PSU.

[Iggy Wolf]

Honestly, I wouldn't know how to do that. I'm not too tech savvy with the BIOS. Although I think if it was my CPU fan, the PC would have simply shut down in order to prevent overheating. To clarify, it started AFTER exiting playing GTA V, a naturally demanding game that raises temps for everything. My GPU fan safely slowed down to 10% after exiting.

I checked my CPU cores' heat by using the Core Temp program. All showed a consistent safe 37 degrees Celcius. That simply leaves my PSU and case cooling fans as the culprits. And as you said, I can't control the PSU's fan. I've have to have the case open while it's running to see which one is the culprit. But thanks for the advice though.

[Iggy Wolf]

To clarify, this is the noise it makes. I'm guessing it could be bearings, but I don't know which fan is the culprit, and I'm unlikely to find out until the system itself tells me or it maintains that noise consistently (rather than after heavy usage) (CPU fan failure, system shutdown, or overheating etc.): https://www.youtube.com/watch?v=Th81Tmj3URE

[Big Boom Boom]

Go into BIOS, fan control. Turn on the fan to full speed and listen. Look in the manual if you don't know where.

To check GPU fan, go into the ASUS software, fan curve, change the curve to 70% and listen. Shouldn't need to change to 100%.

My guess is it's the GPU fans.

[Iggy Wolf]

My dad gave a listen and it turns out it's the PSU. Not the fan though. The bearings have gotten weak. Not too much of a problem. In any case, if necessary, I'll simply buy a new PSU. I know PSU and PCs automatically shut down anyway should the PSU fail. My old computer's PSU did the same thing, where eventually the fan was turning on and off, leading to the PSU overheating. Although in that case, the grinding was consistant everytime I turned on the PC.