My first build, CPU Fan error, Advice Appreciated

[strawberry_fool]

Hello,

I probably sound like an echo to you all in here but I appreciate any guidance you can offer. Recently assembled my first machine with parts ordered from Newegg. The first time I fired it up all the fans were running including the HSF but I got a "CPU Over Temperature Error" so I shut it down immediately and did some investigation. I suspected that while installing the stock HSF I may have mucked up the compound by seating and then reseating it to more cleanly run the fan cable to the connector. Ok, first lesson learned...

Next I started to question the stock Intel HSF and decided even if it does work acceptably when properly installed it couldn't hurt to get a better performing device to protect my CPU. So I ordered the Arctic Cooling 13 and the Arctic Clean kit to remove the old compound and purify the surface. Last night I cleaned off the old thermal compound and installed the new cooler using the pre-applied thermal pad and when I fired the box up it was giving me a "CPU Fan Error." The cooler fan was running and I did leave the machine on briefly to look around the EFI BIOS and it showed the 3 case fans active and the CPU Fan entry looked as if it hadn't detected one... The temperature already was already near 100 and going up though I restarted once and it was not giving the CPU Over Temp error, still just the cpu fan error.

Below are my build specs. I assume my next step is to remove the cooler, clean the thermal pad and re-apply compound myself. Any other thoughts, ideas or suggestions before I proceed? Thanks in advance!

MB ASUS|P8Z68-V PRO Z68 LGA1155 R
CPU INTEL|CORE I5 2500K 3.3G 6M R
VGA MSI|R5770 HAWK 1G RT
PSU CORSAIR|650W CMPSU-650TXV2 R
CASE LIANLI|PC-K7B RT

 

[rolli59]

If the CPU fan is plugged in correctly then there is a possibility that your board has a faulty thermal sensor and is giving you false readings as well as not reading that the fan is connected.

 

[Soma42]

Check to see where your fan is connected. Make sure it's not connected to the chassis fan or power. Also, the CPU fan should be a 4 pin connector and if you have a 3 pin fan then you should make sure it's connected on pins 1,2,3.

From Intel:

Pin 4-Wire Support Pin 3-Wire Support
1 Ground 3 Ground
2 +12 V 2 FAN_POWER
3 FAN_TACH 1 FAN_TACH
4 FAN_CONTROL N/A N/A

http://www.intel.com/support/motherboards/desktop/sb/cs-012074.htm

 

[strawberry_fool]

Ok ere are 2 CPU Fan connectors on the board labeled as CPU_FAN_OPT and CPU_FAN, both 4 pin.

I was connected to CPU_FAN_OPT and after switching to CPU_FAN and powering up the fan is detected.

Fan is running at over 1600rpm and BIOS is showing the CPU temperature at 120F / 49C. It's been idling for a few minutes now.

Do these temps seem ok? I feel like they're a little high.

Thanks again.

 

[008Rohit]

Ok ere are 2 CPU Fan connectors on the board labeled as CPU_FAN_OPT and CPU_FAN, both 4 pin.

I was connected to CPU_FAN_OPT and after switching to CPU_FAN and powering up the fan is detected.

Fan is running at over 1600rpm and BIOS is showing the CPU temperature at 120F / 49C. It's been idling for a few minutes now.

Do these temps seem ok? I feel like they're a little high.

Thanks again.

BIOS false reports most of the times.
Check with RealTemp or CPU Thermometer.

40-45C is fine at idle if you live in a hot country.

Like, My i3 2100 heats up to 75C while playing heavy games because I didn't buy a seperate GPU.

 

[Soma42]

Yeah double check with RealTemp or something. My bios temps are off by a few degrees usually (5C or so).

Are you using stock the stock cooler? Did you apply the thermal paste correctly?

It might not be seated properly, but that usually gives much higher temps...

The OPT in CPU_FAN_OPT stands for optional, as far as I know, and is used for push-pull setups with the fans linked to eachother. Correct me if I'm wrong, but I'm pretty sure that's it. You should only use the CPU_FAN_OPT if you have a second CPU fan.

 

[008Rohit]

Yeah double check with RealTemp or something. My bios temps are off by a few degrees usually (5C or so).

Are you using stock the stock cooler? Did you apply the thermal paste correctly?

It might not be seated properly, but that usually gives much higher temps...

The OPT in CPU_FAN_OPT stands for optional, as far as I know, and is used for push-pull setups with the fans linked to eachother. Correct me if I'm wrong, but I'm pretty sure that's it. You should only use the CPU_FAN_OPT if you have a second CPU fan.

1. The thermal paste comes pre-applied on the heatsink with newer CPUs.
2. umm.. dunno why, but my DH61WW board doesn't have that cpu_opt connector.

 

[Soma42]

not all boards have the OPT connector. I don't think mine does either

 

[strawberry_fool]

Thanks all for the replies. I looked through my Asus manual and can't find any explanation for the cpu_opt connector...

I did break down my machine one last time, thoroughly cleaned the CPU and heat sink and applied Arctic Silver 5. The 3rd time around I was much more savvy at seating the cooler without it slipping around while I tried to thread the screws.

Upon powering up this time the BIOS temps were even hotter but I was skeptical because the heatsink didn't feel warm at all after leaving it idle for around 20 minutes. All the fans were running and I didn't get any temp errors or warnings.

I decided to proceed and install Windows and afterward I downloaded a temperature utility and all 4 cores were running at 32C while at idle and so far not higher than 47C while under load...haven't tested heavy load yet but I feel much better now.

Thanks again.