DS411Slim overheating fix attempt #2 (added heatsink)

I’ve reported earlier that my DS411Slim started to have critical overheating problems and that I did replace the 3 years old system fan without success.

In this second fix attempt I purchased a thermal adhesive from Akasa and using a filer I adapted a heat sink that I had hanging around so that it would fit with the bolts that keep the heat spreader attached to the electronic board.

High hopes as before, but the file compression test failed again. The interface is working and the heat sink gets very hot.
Unfortunately it seems that the more heat I remove from the CPU the more gets generated.
Indexing videos generated the very same behavior.

I’m running out of ideas and I’m starting to challenge the idea of getting a DS414Slim to make a fail-resistant setup.
I see no point in investing in another Synology as the first one is constantly failing.
It is too bad because the management software is very nice and powerful.

Anyone that has an idea on what to try next is welcome to comment to this post.

Below are a few snapshot of the hack.

Factory fit heat spreader with connecting bolts that require heat sink adaptation.

1st corner of the heat sink filed

2nd corner filed

Interference check with the filed heat sink before bonding

Side view of the bonded heat sink

Side view with the 3 drives in place before the insertion of the empty disk frame.

7 thoughts on “DS411Slim overheating fix attempt #2 (added heatsink)

  1. Hi Marco I see you are very keen on mods, did you play with the DS on terminal? I need a little help from a working unit to recover my DS! Regards.


    • Hi Mihail,
      yes I did work a bit with the terminal interface when the 411Slim was still alive.
      Do you need to recover the DS from the point of view of the software (like in a broken installation) or to recover the data stored in the disks?


      • Mine is blinking blue no signs of life in it. After done some reading on synology community forum and test the board trying connecting via serial interface. Definitely something went wrong with the flash chip. Maybe the installation is broken because the unit is a gift from a friend.


        • What worked for me when the unit was stuck was the following sequence:
          1) with the unit off pull all the existing disks and put in a non-synology-zed one (any size will do)
          2) reset the unit with the reset button as per the specific unit instructions
          3) install DSM from scratch on the newly inserted disk using the desktop utility.
          After these steps the DSM was operating again.

          If subsequently putting back in the old disks makes the DS to fail to recover the data in the old disks you can mount them on a linux machine using LVM.


  2. Hello Marco, Did this heatsink fix all the overheating problems for you? I’ve looked over the boot messages through serial connection, I’ve tested the memory from U-boot and came to conclusion that my unit overheats too, until the processor is blocking. I’m thinking of applying a heatsink from a laptop with heatpipe, directly to the processor maybe that will help. I think mine has problem with the thermal paste/pad between the processor and current heatsink.


    • No, unfortunately the heatsink was not enough.
      I did replace the thermal paste (the operation needed the unsoldering of the factory heat spreader) and the termal pad is doing his job: the end of the heatsink fins become extremely hot.

      To me it looks like something else failed in the electronic board (I guess some condenser or a voltage regulator) thus leading to abnormal heat generation in the CPU.
      I don’t have the needed electronics tools and skills to get to that level, but if you have a knowledgeable friend with the tools it might be worth asking him to check the voltages on the key parts of the board.


      • Ok, thanks for the info. Then I will need to check the board again. There were no signs of burn, I’ve already checked that. Also the power supply seems good, delivering the 12 volts under load.


Comments are closed.