XPS 420 CPU Fan

Hi 6ixtythree,

Good work on the troubleshooting, I’d suggest you to run the diagnostics on the computer by following the steps mentioned below and check if there is any issue with the hardware on your system.

1. Turn on or restart the computer.
2. Immediately at the Dell logo screen, starting tapping the key once a second until the One Time Boot menu appears (if the computer boots to Windows turn the computer off and try again).
3. At the One Time Boot menu, press the arrow key to highlight Diagnostics, PSA+ or Enter ePSA, then press to begin the PSA.
4. Write down any error codes listed. Reply to us with the error codes.

If there are no error codes during the diagnostics you can consider replacing the heat sink and fan assembly on the computer.

Thanks for the reply Ravi

I ran the diagnostics, Pre-Boot Assessment Build 4510, including the optional memory tests with no error codes. The final message was something like - Complete. No Diagnostic Utility Partition found. OK to reboot.

Can the heat sink fail?? I thought it was just a lump of metal.

Is there a sensor that detects the air temp??

I have been looking on the Dell site (product support) for spare parts but can only see memory or accessories.

I was trying to get the cost of any new bits as it may not be worth repairing if the new parts are quite expensive.

Thanks once more for your help

Hi 6ixtythree,

Heat sink and fan come has one combination. So the issue seems to be with the Heat sink and fan assembly. Please consider replacing it by contacting our spare parts division at 1-800-357-3355 (US only). Yes there is sensor which detects the air temperature in the system.

Thanks Dell Chavi

Can you tell me if the sensor is part of the motherboard. I really did not want to replace the heat sink and fan if it is a sensor problem somewhere else.

I have replaced the fan with a second hand one from eBay but the problem is still there.

Thanks

Dave

Hi Dave,

I would suggest you to replace the entire set of heat sink and fan assembly on the system. Also, I would like to know if you are experiencing any heat issues on the system and if it’s powering off. If yes, do let me know the duration of the system in the ON state. 

Thanks Dell Ravi

I have just checked the temps (HW Monitor) and these are showing as core#0 96(F), core#1 102(F), core#2 87(F), core#3 87(F). The machine has been on for over 2 hours. Not running anything heavy, mainly MS Visual Studio.

I am not having any problems with powering off ( I just need to get away from the noise every 10 minutes or so).

I will have to call Dell UK for a price. I cant seem to get my service tag recognised by the Dell system. I type in the number and it picks up as a XPS 420 but when I go further for parts etc the tag is not recognised. I did format the HDD when I updated to Win 7 some years ago. The system checker also fails with an error message.

Hi Dave,

The temperatures on the system seem to be normal. You will have to contact Dell UK at Call:  0844-338-1000 (8 a.m.–8 p.m. Monday–Friday) for purchasing Heat sink and fan assembly.

I have the same issue. I would like to attempt to clean the sensor first. Can you explain please where exactly the sensor is located for this system?

Hi Ravi,

I have been researching this topic relentlessly on the web and this is the closest thing to an answer for the problem I have found.  The only thing is, the answer you give the original poster is incomplete.  Unless the sensor is on the fan/heatsink assembly, changing them will not do a bit of good.  He already mentioned he changed them out with a replacement purchased on ebay.  So my problem is exactly the same except that my card fan also ramps up and runs on high speed.  Temps are all normal.  It is obvious it is the temp sensor that is not working properly.  Yet i am unable to find any info as to where it is located or if it can even be changed by the average user.  It is a shame because except for this horrible noise that sounds like a vacuum cleaner running, the computer still works flawlessly after all these years.  If you are indeed a Dell Tech and not a salesman, could you please reveal the bit of information that I have futilely searched for on the internet?  If I can't get it, then I'm sure I will never be purchasing any Dell products in the future.

That is a good post Cemprasad.

When I spoke with Dell I queried the need to swap out the heat sink as there was no sensors on it. I could not be sure about the fan but a new one did not make ant difference. I am sure all Dell want is for themselves to do a repair and for us to pay a lot of money for it.

I hope Dell do answer your post with something useful.