11 Replies Latest reply on Sep 11, 2012 6:07 PM by Jon Thurgood

    i5 3570K Heatsink Issue/Question


      So I recently built my first rig, and everything seemed to be running fine at first. For purposes of this topic, the Motherboard I'm using is the Asus Sabertooth Z77, and the CPU is the i5 ivy bridge 3570K.


      The issue I'm running into now is that the CPU fan seems to only run occasionally (maybe after a few boots or so, or only after I've had my computer running for a bit). I'm new to computer builds and all the components, but I would've assumed that the CPU fan would run non-stop? Usually when I boot up windows, I get an error message in the bottom right hand corner, that informs me that my CPU fan is running at 0 RPM's. When I monitor the fan using the Asus AI Suite, the CPU fan reads as N/A, but then will occasionally spin. Even without my CP fan running, my CPU idles at around 35-40 degrees. I ordered a Corsair Hyper 212 evo, because I'm assuming that its just a faulty heatsink. I've made sure the connections are all solid, etc, so any other tips would be greatly appreciated. Like I said though, if I boot up my computer, the fan kind of stutters like its trying to power itself up, but it fails to.

      Not sure if theres a setting in BiOS or something like that, or if its a specific feature that the fan only runs when it hits a certain temperature (like a toggle  setting somewhere?), but I'm not sure.



        • 1. Re: i5 3570K Heatsink Issue/Question

          Processor fans run between 900rpms – 3000rpms depending on the processor’s load and temperature.

          For troubleshooting purposes:

          1. 1- Test the fan on a different case fan header. If issue replicates, your fan is having issues.

          If the fan is properly working on another fan header:

          1. 1- Make sure your motherboard has the latest BIOS version for it to load the latest micro code available for your processor for a proper recognition of it.
          2. 2- Contact your motherboard manufacturer for warranty assistance

          If needed, please proceed to contact your local support group during business hours: http://www.intel.com/p/en_US/support/contact/phone

          • 2. Re: i5 3570K Heatsink Issue/Question

            I understand that, and I have tried those options. I ordered an after-market heatsink, and I'm waiting for it to arrive. Just going to test it out, to see if in fact it is a defective heatsink I received. 


            The issue isn't that my CPU fan is completely obsolete, instead, it just runs whenever it feels necessary. If I power on my machine and just boot up windows for instance, my fan just seems to stutter, and doesn't run. If I decide to play a game, install, or download something, it runs perfectly fine (around 1100 RPM's or so). I was wondering if theres some type of setting that is making it selectively run? Also, is it common for CPU fans to be running non-stop, all the time?

            • 3. Re: i5 3570K Heatsink Issue/Question

              The stock fans with this processor seem to be quirky.  I have the stock one installed and it runs at the same RPM no matter what the load is on the computer.  At idle it is running between 900-1000RPMs and when I run the Intel XTU Stress test the processor heats up to around 75 Deg C but the fan still runs at 1000RPM.  I can't get it to run any higher no matter what load I put on it.  Brad, how did the A/M fan work out for ya, did to function correctly?

              • 4. Re: i5 3570K Heatsink Issue/Question

                I suggest checking a few things before deciding the CPU fan is bad. First, it must be connected to a four pin PWM fan header, which should be labeled the CPU Fan on your board. Next, you must check and adjust the CPU fan speed control in your boards BIOS/UEFI, or with your boards fan speed control software. The PWM fans used on the standard Intel CPU coolers have been used for years, and short of being defective, should work fine and change speed along with the CPU temperature, as long as the CPU fan speed control is configured correctly.


                What mother board are you using, and what are you using to monitor the CPU fan speed?

                • 5. Re: i5 3570K Heatsink Issue/Question

                  I am running the i5-3750K on a DZ68BC MB.  I have been using the Intel XTU and Speedfan to monitor the temps and speeds.  I got to looking around inside of Speedfan after I seen your post and just noticed that there is a setting that in the new version defaults to an automatic fan control.  If I change it to manual I can then change the speeds of the fans and got the CPU fan to run at max RPMs.  Thanks for the tips.

                  • 6. Re: i5 3570K Heatsink Issue/Question

                    John, that's great. I suspect that the CPU fan control settings in the UEFI/BIOS could be changed to enable automatic CPU fan speed control, if you want to use it that way.

                    • 7. Re: i5 3570K Heatsink Issue/Question
                      Jon Thurgood

                      I've been having similar problems with the stock CPU Fan with this CPU. When I turn on the computer, I can hear the fan rev up to high-speed and then slow down to idle. When I get to check the speed in the BIOS, it's idling at around 1800 RPM. If I load up Windows 7, it seems to hover around the same speed. However, if I run a CPU stress-test, the fan speed actually SLOWS DOWN to 1100 RPM, and the CPU starts overheating to 80C. I have tried all the settings in in the BIOS, and all the available headers on the board. Even if I tell the system to keep the fan at 100%, it still does the same thing. I don't think the fan is reading the voltage changes properly.


                      I tried plugging a different fan in the same headers from another CPU cooler I had around, and the speed did not change, so I don't believe it's the motherboard or BIOS settings.

                      • 8. Re: i5 3570K Heatsink Issue/Question

                        Jon, what utility are you using to monitor the Fan RPM?  Your situation may be the similar to the one that I had, the issue was not with the fan, the board or the BIOS.  It was the Fan Control Utility that is was using (In this case SpeedFan), it was defaulting the the fans to an automatic setting and that setting wasn't compatible with the DZ68BC board I was using so it would cause false readings.  The Temps would also be funny, that is how I figured out it was the utility, sometimes I would get temps of over 200 Deg F for the PCH and the difference in temps on the 4 cores would be more than 10 Deg F, on a fresh start. 

                        • 9. Re: i5 3570K Heatsink Issue/Question
                          Jon Thurgood

                          For fan speed, I'm using the BIOS hardware monitor screen to find the idle speed. When the OS is running, I'm actually monitoring the fan by sight and sound (cover off), so I'm guessing at the 1100 RPM, but I can definitely tell it's slowing down under stress, which is very strange. I have tried the MB headers which are not controllable (should be constant power), and it does the same thing there. Someone said that it's monitoring the voltage drop to speed it up or something? Anyway, for temperature, I'm using Core Temp 0.99.7. I guess the only way to know for sure is to put a volt meter on it. Anyway, it's a brand new board (MSI Z77A-G45), with all the latest drivers and BIOS (V2.50). I'm going to see if I can find a utility to monitor the fan while running the OS.

                          • 10. Re: i5 3570K Heatsink Issue/Question

                            Well the MB Fan Headers are controllable, you just have to use 3rd party software, like SpeedFan, to do it.  As for the voltages, if you are using a PWM fan (4-Pin) than there is a constant voltage to the fan and the speed is controlled by a signal provided by the 4th pin which is either a 5v or 3.3v pin.  If you are using a conventional fan (3-Pin) than the speed of the fan is controlled by the voltage running to it, i.e. the higher the voltage, the faster the fan runs.  If you have the 3-Pin fans connected to the MB, and they are not acting as you think they should, check in the BIOS in the Cooling Section and make sure that the fan voltages, the Min/Max, and the Speed Adjustment mode are all set correctly.  Having these settings incorrect can cause the fans to not run properly and can damage your hardware.  The fan that comes with the CPU is a 4-Pin PWM Fan, and I believe the header provides a higher voltage than the other ones, that is why it is recommended not to connect a regular fan to the CPU Header.  Try using SpeedFan, just Google it, to control the fans.  Once you get it installed, go to the config section, and the Advanced tab I believe, and select the motherboard from the drop down.  There will be 3 PWM Fan Mode settings that will be defaulted to Smart Fan IV.  If you change them to Manual, you can adjust the speeds of the fans on the main window of the SpeedFan GUI.  SpeedFan also monitors Temps, and Voltages too, so you only need to run one monitoring program.  Hope this helps ya.

                            • 11. Re: i5 3570K Heatsink Issue/Question
                              Jon Thurgood

                              Thank you so much for suggesting this program. I have been able to tweak my fan control to get a faster speed, but in a very weird way.


                              I notice that if I unplug the fan and plug it back in (or stick finger in fan to stop it), that when it will stop for a couple of seconds and then try to start up. It will jump to over 3500 RPM for a couple of seconds and then settle down at 2000 RPM. With the fan control program (SpeedFan), I have been able to tweak the fan to run at 2700 RPM continuously as a maximum, and I had to set it to run at 68%. Any lower, and the fan will slow down and stop running at anything below 60%. Any higher, and then fan will gradually slow down until I hit 100% where it will run at 2000 RPM. VERY weird. Oh, and this was on the SysFan2 port and not the CPU Fan port as I seem to get better results.


                              Anyway, I guess I'll wait for a new firmware release or something to see if that helps.