What would happen if a machinist with a knack for fine detail took on the task of lapping a 16-core CPU? The result is the smoothest surface ever on the processor's integrated heat spreader (IHS). So smooth, in fact, that it can be installed on a PC without thermal paste.

Let's back up a bit and take a high-level overview of the CPU cooling mechanism. The big hunk of metal at the top is the IHS, which has two purposes.

to pull heat up from the CPU die and transfer it to the cooling block (usually an air or liquid cooler).

However, the surface of the IHS is imperfect, and the same is true when installing a heat sink. This is where thermal paste comes into play. Thermal paste is a conductive material that fills the microscopic irregularities in the IHS and heat sinks and facilitates heat transfer.

While effective for mass consumption, as with most things produced on a large scale, there is room for improvement for those with the necessary knowledge, money, and time. This is where the method of wrapping comes in.

If you examine the videos and articles on lapping, the majority of what you will find is really good-looking sanding. This involves hand sanding the IHS of the CPU to smooth the surface, which I have done myself in the past and can certainly lower the temperature by a few degrees.

Simon Penrow, a machinist with a YouTube channel, pursued the idea of really lapping the CPU. In doing so, he estimates that he has "brought the flatness error of the Ryzen 9 3950X to within 0.3 microns, making it the flattest CPU in the world."

For reference, this is two orders of magnitude higher than the accuracy that can be achieved with sandpaper alone.

He partially documents the process in a 10-minute video, detailing the various steps in a very calm voice. Seriously, I could hear him reading the phone book (remember that?)

Penlow created his own wrapping plate for this venture. As Penlow points out, this plate must be softer than the work piece (in this case, the metal top of the CPU). It also needs to have a checkerboard-like groove so that the shaved bits do not fall into the gap and disturb the soft, flat surface.

In an interview with Sweclockers, Penrow said it took about six months from start to finish. He also explained how he became interested in wrapping in the first place. [Silicon temperature is a key factor limiting the turbo frequency of the Zen 2 processor, and when I installed a second radiator without noticing the huge temperature difference from before, I started looking at other solutions.

Penrowe claims that he did not have time to test the temperature results of his efforts and create lots of graphs, but he does give notice at the end of the video that someone else who currently owns the CPU will be doing it for him. In the near future, it will be known if the CPU will work without the thermal paste.