Thermal Throttling

Due to the compact form factor, M.2 drives lack the ability to actively cool themselves, usually having 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, installed 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 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 that generates some airflow around the CPU socket.

Reads

Writes

There's no thermal throttling at all, very good. The drive has two temperature sensors: red line = flash temperature, green line = controller temperature.

Thermal Image & Hot Spot

We recorded a thermal image of the running SSD as it was completing the write test. The hottest part on the drive reached 89°C. The drive's own thermal sensor reported 92°C for the controller at this time, which is pretty close to the actual temperature. We've seen some drives misreport temperatures by up to 30°C. Temperature on the 1 TB drive was a little bit lower, but the differences are minimal.