The Samsung Tech Days not only brought us news about future RAM memory standards, but they also talked about their NAND Flash memory, especially their V7 QLC with which they hope to improve the performance of the NVMe and SATA SSDs they use. per cell for storage. What are its performances and what news does it bring?
There is no doubt that the big challenge with using non-volatile RAM for storage is precisely the cost per bit stored, which is much higher than conventional hard drives and prevents their transition. Although 5-bit per cell chips are on the roadmap, for now the maximum that has been achieved is reaching QLC memory with 4.
Well, during its Tech Days 2021, Samsung showed off its new NAND Flash memory for personal computers, which we will soon see installed inside the SSD. So let’s see what its performance is.
How is the Samsung V7 QLC?
First of all, we must point out that the NAND Flash V7 QLC of Samsung is integrated 176 covers and it is therefore QLC 3D NAND. So right off the bat, the storage capacity should at least double, since Samsung’s V-NAND memory currently uses 96 layers.
Although the most important thing here is its performance, Samsung claims that the write speed will increase. 2.7 times and read about 2.6 times. This is the key to building cheaper NVMe SSDs that don’t require the use of so many memory channels and thus open up the capacity to cheaper drives.
On the other hand, despite the fact that PCI Express 5.0 compatible SSDs are still somewhat distant in time, it should not be forgotten that said bandwidth is achieved between the flash controller and the system RAM via said interface. The data is in the NAND Flash chips and not scaling it up in speed is a huge bottleneck in terms of the performance of this type of unit.
The future of SSDs is in QLC
The title is not our words but those of Samsung itself who said that, like TLC memory, they not only expect most PC SSDs to use QLC cells, but also for mobile devices and for both memories and UFS used as storage. also the transition to this type of cells.
The key to making this transition will be to increase the capacity of the SLC cache to support higher read and write volumes. Let’s not forget that the increased bandwidth will fill up faster, drastically reducing performance. For example, as the picture shows, the Samsung QLC-SSD 870 QVO reduces your bandwidth to 160MB / s when the SLC cache runs out due to its small size, a speed too low to be a significant advantage over conventional hard drives.
They hope to solve this 4-bit NAND Flash performance issue with the ability of the Q7 VLC to run at speeds of around 500MB / s with the SLC Cache full, so SSDs using this type of NAND Flash will eventually gain market share.
