Did CPU of my TC-895-UA91 start overheating?

Piero1

I own an Acer TC-895-UA91 desktop running Windows 10 Home 64-bit.

Lately the CPU fan speeds up almost continuously (at about 680 rpm indicated by Speccy) and it's very noise. I wonder whether my CPU is overheating as Speccy shows CPU temperature between 43 and 55 Centigrade when the problem occurs. Motherboard voltages show as:

  Voltage
    CPU CORE    1.632 V
    MEMORY CONTROLLER    1.760 V
    +3.3V    2.976 V
    +5V    5.000 V
    +12V    11.904 V
    -12V    -11.968 V
    -5V    -9.408 V
    +5V HIGH THRESHOLD    4.032 V

and....that -5V at -9.408 concerns me a little. Everything else works just fine!!  

Any suggestion? - Piero

billsey

-5V at -9.xV is usually just that there's not enough of a load to sample accurate figures. Your best next step is to do as ttttt suggests and run an actual temperature monitor program. I use Core Temp because it's a bit smaller than CPUID. Normally fan noise at that slow of a speed (680 RPM is barely turning over, full speed is likely more like 3600 or 4800 RPM) point to a bearing going out or excessive dust buildup on the blades. Do a good vacuum (while the computer is off) of both the fan and the heatsink it mounts to to see if that helps enough. If not, those fans aren't very expensive...

ttttt

@Piero1

If you download and run CUPID Hwmonitor you can tell the temperature of your CPU and the fan speed. 680 RPM speed is actually rather normal for CPU fan speed not under heavy load.

It can be as high as 3000 RPM under load and high ambient temperature condition. If the CPU temperature is nothing higher than 80 degree C under load, it is not alarming .

Probably bearing worn out or unbalanced weight by dust build up. Try to spray with a can of compressed air to clean the dust on the CPU fan first.
Apply new thermal paste to the CPU fan if the fan is still loud. If problem persists, replace the CPU fan. 

Larryodie

My -5V reads high too. 9.34 on TC-895-UA92. Temps read between 29C and 32C. The fan speed is constant at 202 RPM

billsey

-5V at -9.xV is usually just that there's not enough of a load to sample accurate figures. Your best next step is to do as ttttt suggests and run an actual temperature monitor program. I use Core Temp because it's a bit smaller than CPUID. Normally fan noise at that slow of a speed (680 RPM is barely turning over, full speed is likely more like 3600 or 4800 RPM) point to a bearing going out or excessive dust buildup on the blades. Do a good vacuum (while the computer is off) of both the fan and the heatsink it mounts to to see if that helps enough. If not, those fans aren't very expensive...

Larryodie

Here is my Bios readout. The RPM is 804 to 805. Steady. My room temp is now 77 degrees. 
@Piero1, as Billsey recommended clean and replace any  noisy fans. If you can't find a replacement put a drop of ATF oil on the bearing via a toothpick.

Piero1

Picture is covering part of your response. However in what fan should I put the drop of ATF oil? The CPU fan or the PSU little fan?Thanks any way for your help - Piero

Larryodie

I fixed the previous post
Are they both noisy ? You should be able to turn them by hand and feel the drag if the bearing is dry.
Automatic Transmission oil is very thin but any light oil will do, providing you have an opening to drop into the bearing.
These fans motors are probably under $10. 
Google or Ebay search on the manufacturers number. Mouser.com or digikey.com should have them too. Good Luck. 
Acer may have them too.  https://store.acer.com/index.html

billsey

Normally it's the CPU fan, the PSU fan usually runs at a fixed speed, while the CPU fan varies it's speed based on CPU temperature. You can see Larry is at 51C while in the BIOS, so under about as small of a load as possible, and that temperature is ideal. My laptop tends to run in the middle to upper 50s with a couple of hundred processes running, as listed in Task Manager.