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 and the M.2 slot between the CPU and VGA card. A second data point shows the result with a 120 mm fan directly blowing on the tested 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

Even with a fan blowing right onto it, the M480 thermally throttles—a first for our SSD reviews, even if it's just a bit. Without the fan, thermal throttling in our stress test happens very quickly. Compared to other Phison E18 SSDs, MSI seems to have set a more conservative thermal limit.

Once the heatsink is installed, there's no more thermal throttling, which is really nice!

Thermal Image & Hot Spot

We recorded a thermal image of the running SSD as it was completing the write test. The hottest part reached 108°C when the drive's own thermal measurements reported 68°C—a huge difference. Once the heatsink was installed, temperatures dropped considerably.