It appears that Crucial started outfitting P2 SSDs with qlc nand, while it was initially released with tlc chips. It’s not clear if Crucial has completely moved to qlc-nand, or if the company is still producing tlc variants at the same time.

qlc variables observed and tested by Tom’s devices, indicating that the performance is much lower than that of TLC models. Besides using qlc-nand , it was not critical to change anything about the drives. So the model name remains the same. As a result, users cannot know in advance which variant they are purchasing. Additionally, many of the reviews are based on faster TLC models, which can lead to confusion.

According to Tom’s Hardware, differences in performance are different for each test, but in some tests a P2 drive with qlc will be four times less than the tlc variant, for example when burning a 6.5GB zip file. Additionally, the qlc model achieved a speed of 98MB/s, compared to 428MB/s with the original Crucial P2. Also on DiskBench running a 50GB file, the qlc drive is noticeably slower.

The qlc model also has a larger slc cache, 135 GB compared to the 24 GB of the P2 with tlc-nand. However, the TLC variant was faster, and the write speeds of the QLC variant decreased more than the TLC variant after the SLC cache was full.

Crucial informs Tom’s Hardware that it has considered a potential switch to qlc-nand in its performance claims. At release, the manufacturer announced write speeds of 940 MB / s, while according to Tom’s Hardware in practice, they are 2 times higher on a P2 500GB SSD with tlc-nand. QLC’s performance will be more in line with the advertised speeds.

It is also unknown if Crucial only produces qlc variants from a P2 SSD. Crucial already mentioned in a statement in 2020 that it could eventually switch to “a combination of tlc and qlc.” company Reported to PC Gamer last year: “The Crucial P2 SSD currently uses Microns tlc memory, but over time it may contain a mix of Microns tlc and qlc nand. By mixing nand types with different capacities, we can make product customizations and—making decisions based on emerging and Changing technology, preferred capabilities, and flexibility to align with aggregate market movements.”