840 EVO and 850 EVO employ Turbo Write technology, which increases the write speed of low-capacity 3Bit MLC SSD by using internal SLC buffering to improve performance.
The technology does not write directly into 3Bit MLC; instead, it writes to the SLC Buffering area. Data is moved to 3Bit MLC when the SSD is not writing/reading, freeing up space in the SLC Buffering area.
Analysis of the usage pattern of actual users revealed that about 1.17GB is written per hour on average. Since most users write less than 3GB per hour, which 840 EVO and 850 EVO is capable of, a decrease in writing performance caused by insufficient SLC Buffering area does not occur. (Size of the SLC area differs for each model, but ample space is provided, ranging from 3 to 12GB.)
For further details, please visit the website below and refer to the white paper on Turbo Write
- Turbo Write