The impact of temperature on the lifespan of an SSD

Recently, I tested the WD Black SN750 M.2 SSD with and without a heatsink. The version without heatsink reached 60°C. The SSD with heatsink, on the other hand, only managed 36°C. User Schnaiky asked:

I've been asking myself the same question. In the course of my research, I came across several articles about SSD temperatures. Basically, it's important to differentiate between the storage temperature of SSDs - data retention - and the operating temperature. In many articles about temperatures, information about data retention is used incorrectly, although it is only applicable in very rare cases.

Data retention

Data retention refers to how long data can be stored at different temperatures at the end of an SSD's lifetime. End of life is when the SSD has reached its maximum number of write and erase cycles. Incidentally, this takes lots of time. At lower temperatures, data is stored for longer. The cells in NAND flash, the type of memory in SSDs, discharge more quickly at higher temperatures. According to the JEDEC, the standards body for SSDs, data is stored for 365 days at 40°C. And only 2 days at 85°C. Find out more about data storage here.

Operating temperature

Data retention explicitly applies to SSDs that have reached the maximum number of write and erase cycles, i.e. on which data is stored. I haven't found any reliable figures for ordinary uptime. Data retention specifications do not apply to the proper operation of SSDs.

Operating temperature behaves inversely to data retention. Conventional NAND flash memory is designed to withstand temperatures between -40°C and 85°C. The maximum temperatures in this spectrum favour writing to and erasing from the memory: at lower temperatures, the NAND cells are more stressed by the write and erase processes.

Temperatures of up to 85°C do not currently have a negative influence on NAND cells. According to a study, high temperatures may even be beneficial to them. One study proves that if NAND cells are exposed to 800°C for a short time, they regenerate when they reach the end of their life. I have not found any precise information on the temperature at which NAND flash cells are actually affected.

High temperatures are no problem for NAND flash during operation. However, according to manufacturers, many SSDs are only designed to operate between 0°C and 70°C. This is due to electronic components such as the controller. As with the CPU and GPU, the controller in an SSD should not get too hot.

In a promotional article about WD SSDs by my colleague Jan Heidenreich, user Flashbin mentioned a Gamers Nexus video.

In the video, Steve Burke recommends that when using cooling elements for SSDs, thermal pads should only be attached to the controller. NAND chips should not be actively or passively cooled.

What is the ideal temperature?

What does this mean for the recommended operating temperature? Temperatures between 30°C and 50°C under load are perfectly normal. If the SSD gets a little warmer for a few minutes under load, for example at 60°C as in my SN750 test, there's nothing to worry about. However, if the SSD is constantly running above 50°C at idle, you need to change something about the cooling. According to Computer Base (in German), in the SN750, thermal throttling appears at 81°C. In other words: the SSD slows down to cool down and then continues its work. This throttling is not triggered by the NAND flash, which is too hot, but by the controller. If it doesn't happen regularly, a brief rise in temperature in the red zone should therefore have no negative effect on the SSD.