Cpu fan reading low rpm's

A while ago I purchased an Intel E8400 with a gigabyte GA-P35-DS3L/S3L motherboard. Shortly after building it I started noticing that my idling temps were a little high according to the program coretemp (this is the only program I used to check and it idled around 53 degrees C and went up to 70 degrees C when gaming) so I decided to reapply thermal paste since I was using the paste that came with the processor and reseat the hs fan. When I rebooted, and I don't know if this was the problem beforehand or not I guess I did not pay much attention, the cpu fan was running at only around 180-200 rpms. Leaving it in bios for around 10-15 minutes the processor only got to 34 degrees C but the system temperature (don't know if that matters) was raising to around 41.

Also, just to test it I plugged an AMD fan that a friend had into the port and the RPM's were still low at around 300 but they were slightly higher than my Intel readings. I also plugged the cpu fan into a free system fan port and the rpm's were around 800-900 steady while sitting in BIOS.

I ordered a new cpu fan to try out and I'm hoping this fixes the problem but if it doesn't I would like to know what is going on.

My questions are these:

1) Does that sound like a misreading on the speed or is the fan running that slow?

2) If the port is broken, can I use the extra system fan port I have as a backup?

3) How fast should be cpu fan run?

4) Does replacing the fan sound like a good idea?

Now I do not claim to be a computer expert. My computer was assembled under supervision of friends who know more than I do. I just want to fix it if there is a major problem.

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  1. Make sure that you have disabled fan control in BIOS.


    Look under "PC Health Status"
    Then go to "CPU Smart Fan control", set this to "Disable".
  2. Yeah the smart fan control feature is disabled. The fan just sits between 186 and 187 rpm's while the temp fluctuates between 30-31 Celcius. Do a get an accurate idle temp if i'm just in bios?
  3. Run Prime95 Small FFT and see if the fans kick up.
  4. How long should I run it?
  5. 20-30 minutes.
  6. Alright I replaced the stock intel cpu fan with an aftermarket one and the BIOS reports that is running at 216 rpms now which seems low still. I ran Prime95 while I was sleeping last night and I kept Everest open to monitor the temperatures. The strange thing about Everest is that while my BIOS reports my new cpu fan is running at around 216-218 rpms, Everest reports that it is running in the 860-870 rpm range. Anyhow, idle temps reported with Everest are Core 1 = 41 C and Core 2 = 37 C. Seems they jump up to around 60 while running Prime 95. Now I really don't know which temperature program is the best since coretemp reads about 5 degrees hotter and realtemp read 5 degrees cooler than Everest. Here is the screen shot of what I was looking at when I stopped the test this morning.

    Is my BIOS just not reading correctly? I have not yet flashed the BIOS, could it just be an old version that doesn't read right? I want to overclock a little bit but I want to make sure my system is stable first and my temps are in the safe range.

    Thanks for your help so far Shadow....
  7. Looks to me like a defective fan header. Go with the RealTemp readings. Flasing BIOS may help, run CPUZ and see what version you have.
  8. Looks like version F9B.....

    Does it matter if it reads correctly or not? Can I just maybe plug it into the system fan port?
  9. Ah.... that might be a problem. The stablest BIOS version I have tested is the F8f BIOS version. You can't find it on the Gigabyte website, check Google. Yeah, try on another port too.
  10. K i'm using F8f now which did not fix the cpu fan sensor issue so I plugged the fan into a different port and its running at 1462 rpm so that sounds good. However, I ran into a new problem. I accidentally broke a fan blade on the fan!!! It is still keeping it fairly cool now I just need to order a new one.....so stupid hahaha

    But yeah, looks like it is a faulty header and they won't replace mobo for that will they? Not a big deal, it is staying at around 58 C with full load and I even overclocked a little to 3.42. Should I just keep it plugged into the fan that reads the faster speed?
  11. ^Yeah, that should be fine.

    Btw FYI:
    GUIDE: Overclocking On EP/P35-DS3L
  12. Alrighty then. Thanks again for your help Shadow!
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