Fixing an overheating Dell N5110 Inspiron laptop

I own an Dell Inspiron N5110 and its fan has become increasingly louder and more aggressive. I opened up the laptop and managed to reduce the peak temperature by 20°C under load.

I followed in the footsteps of someone else who had a similar problem, and used an iFixit guide to open up my laptop. I used a simple set of screwdrivers, isopropyl alcohol, and new thermal compound.

During the operation

  • I noticed that the dust build up in fan grill was not visible externally. The fan itself had to be unscrewed from the grill to see any sign of it. While there was a significant amount of dust within the grill, there was none elsewhere.
  • The thermal compound on the CPU and GPU was not particularly dry and so it may not have been necessary to replace it, but I had to replace it once I had removed the heatsink from the chips (I believed). I carefully removed the old compound using isopropyl alcohol.
  • The thermal pads became dusty easily, and unfortunately I did not have any replacement.
  • Following the guide, I filled up some holes to prevent air from reaching the keyboard. The heat on the palm rest and left-side of the keyboard was something I particularly wanted to deal with.
  • The chipset is on the top side of the motherboard, underneath the left palm rest area below the keyboard. The chipset, and thus the palm rest, heats up significantly because there is no cooling for the chipset, nor the general area.

Conclusions

The heat issues are mostly solved except for the chipset which really irritates my left hand. Overall,

  • I had a peak temperature drop of 10-20°C (this was measured by two consecutive runs of Unigine Heaven and Cinebench before and after).
  • There was no significant drop in idle temperatures, but the fan no longer spins up when under very light load.
  • The biggest disappointment was the insignificant change in the heat on the surface of the keyboard.

I also tried to use HwInfo64 (IIRC) to control the fan speed to see if I could have any improvements in the palm rest area. There were only two settings available: ~3000 and ~5000:

  • Idle tempeatures hit about 40-45°C, and I did not achieve a significant drop by using a custom aggressive fan profile.
  • The chipset did not cool down at all (grr).

Over the past few years, I have opened up my Dell laptop several times, whether to clean it or to replace the HDD. It’s possible that the problems I’m experiencing now are a result of that. The mount and screws securing the monitor on the left side are broken and the screen now has display problems as it blacks out randomly. In addition, sometimes it refuses to turn on.

So some care should be taken when opening it up :)

A final and interesting side note: The battery is on 60% capacity after five years which is in line with what you might expect.