Dell XPS 15 9560 overheating solved

After 2 years of ownership, I finally have a laptop that works as it should, and the solution is surprisingly simple despite the difficult in trackingdown the issues.

Ultimately, it was a 2-pronged approach with tweaks to both hardware and software. Let's start with the hardware. It's simple, and needs to be done:

Step 1:
The cooling system clogs up with dust, reducing its efficiency considerably. If your laptop fans are running more than they should and you haven't cleaned the fans before, now it a good time to do so. There are plenty of youtube videos stepping you through the process. 

Step 2a:
While you have the back off the laptop, locate the SSD. It has a silicone thermal pad (That probably came off with the case) to keep it from overheating. These pads are designed to efficiently transfer heat, but my SSD has a large insulating sticker on it. Simply removing that sticker before reassembling the laptop will keep the SSD running a lot cooler. 

Step 2b:
Optional - locate the SSD heat transfer pad on the outer case, and carefully peel it off and stick it to the SSD.
Note where the pad sat on the case, and remove the thick insulating black paint from that part of the copper shield. (I used 1000 grit sandpaper) 

Step 3:
Reassemble. (Note: Inspect the battery before closing up the laptop - if any cells are swelling up, you may wish to order a new one)

That's it for the hardware. Enjoy a much quieter laptop as the cooler SSD keeps the fans below full throttle.

Right, now for the software:

The XPS15 has a hardware GPU. For some design reason, it only gets used when the Integrated graphics gets overloaded. I am unsure of the reasoning behind that decision, but it means that processing power is unused for most of the laptop's working life.

Let's make it share some of the load.

Step 1:
Open the NVIDIA Control Panel and navigate to "Manage 3D settings" and the "Program settings" page.

Step 2:
Go through the list of programs and select the programs you use the most, and then tell them to use the NVIDIA processor. Web browsers are a good start. (Note that not all programs have the option of using the GPU.)

Voilà

Extra details explaining what you have done, and why:

In my case, Chrome browser and image editing software quickly filled up my 16gig of system ram which meant there was a lot of pageswapping to and from the SSD which caused it to overheat and slow everything down. (An upgrade to 32gig of memory made no difference)

By forcing programs to use the GPU, the 4gig of VRAM becomes available which reduces the amount of system memory being used and hopefully the need for as much page swapping. 

Removing the sticker from the SSD and the paint from the copper shield has significantly improved the efficiently of the SSD cooling hardware.

I hope this helps others.