Thermal Throttling
Due to the compact form factor, M.2 drives lack the ability to cool themselves and usually have to rely on passive airflow instead. All vendors include some form of thermal throttling on their drives as a safeguard, which limits throughput once a certain temperature is exceeded.
On this page, we will investigate whether the tested drive has such a mechanism, how high temperatures get, and what effect this has on performance. We will test the drive in a typical case, in the M.2 slot between the CPU and VGA card, while it's getting hammered by non-stop incoming writes. A first test run, to create a baseline, shows temperature and performance with a 120 mm fan directly blowing on the tested drive. In a second run we'll report thermal performance of the completely uncooled drive. Each of the charts has time moving from left to right, with the blue line displaying transfer speed in MB/s and the red line showing the temperature in degrees Celsius (measured using SMART).
Results from this test setup are
not comparable to our 2019 SSD bench because we're using a different case and a CPU cooler which generates some airflow around the CPU socket.
Reads
Writes
No thermal throttling in any of those tests (without the heatsink).
Once the heatsink was installed, temperatures went down quite a bit, but considering there's no thermal throttling even without the heatsink, it's questionable whether adding the heatsink makes much sense.
Thermal Image & Hot Spot
There's a 20°C difference between installing and not installing the heatsink, mostly because the heat gets spread out over a larger area, so more heat can be dissipated.