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. As a safeguard, all vendors include some form of thermal throttling on their drives, 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 when a 120 mm fan is blowing directly 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 °C (measured using SMART).
Reads
In a pure read scenario, the drive doesn't throttle at all.
Writes
No throttling in writes either—very good. The drop at the start is present in both test runs (with and without fan cooling), so it's not due to temperatures. Rather, it's an effect of the relatively small SLC write cache.