Silicon Motion: SSD controller quintet with PCIe 4.0 for notebooks


Compared to arch-rival Phison, Silicon Motion (SMI) jumped on the train of SSD controllers with PCIe 4.0 late. In the meantime, however, the range is broad, as the manufacturer is demonstrating at the Flash Memory Summit 2022. In addition to new key data for well-known chips, there are two new models without DRAM.

SM2264 on par with Phison E18?

The SM2264 has been known for a long time, but the key data have changed significantly in favor of higher performance. This is also due to the fact that there is now faster NAND flash memory on the market, with which more performance can be accessed. Thus, up to 7.5 GB/s are now in the updated data sheet (PDF), while previously there was talk of a maximum of 6.5 GB/s. In addition to the write rate increased to 7 GB/s, the random IOPS are now over 1 million.

SMI SM2264 Phison E18 Innogrit IG5236 Interface PCIe 4.0 x4 Protocol NVMe 1.4 NAND channel 8 (up to 1,600 MT/s) 8 (up to 1,200 MT/s) DRAM cache ✓ Seq. Read (maximum) 7,500 MB/s 7,400 MB/s Seq. Write (maximum) 7,000 MB/s 7,000 MB/s 6,400 MB/s Random Read (maximum) 1,300,000 IOPS 1,000,000 IOPS 1,000,000 IOPS Random Write (maximum) 1,200,000 IOPS 1,000,000 IOPS 800,000 IOPS

On paper, the SM2264 is practically on par with the Phison E18 and Innogrit IG5236. A first customer is the Adata Legend 960 SSD. But only tests will show where the strengths and weaknesses lie.

The lineup of PCIe 4.0 controllers for the FMS 2022 (image: Silicon Motion)

SM2268XT and SM2269XT without DRAM

The two controllers SM2268XT and SM2269XT were new and presented without a detailed data sheet. At Silicon Motion, the suffix “XT” has so far stood for solutions without their own DRAM cache (DRAM-less), which is why it can be assumed here too that the SSDs have to access part of the main memory via the host memory buffer (HMB).

Both are 4-channel PCIe 4.0 x4 controllers with support for TLC and QLC NAND. However, the SM2268XT is almost in the performance class of the flagship with up to 7.4/6.5 GB/s in sequential read/write and 1.2 million IOPS. The fact that the chip is supposed to support a NAND interface with 3,200 MT/s is amazing, because no other manufacturer advertises with this speed. The highest interface currently available on the market is ONFI 5.0 with 2,400 MT/s with Micron's 232-layer NAND.

SM2267XT SM2267 SM2268XT SM2269XT SM2264 interface PCIe 4.0 x4 protocol NVMe 1.4 NAND -Channel 4 (up to 1,200 MT/s) 4 (up to 3,200 MT/s) 4 (up to 1,600 MT/s) 8 (up to 1,600 MT/s) CE* per channel 4 8 ? ? 8 DRAM Cache – ✓ – – ✓ Seq. Read (maximum) 3,900 MB/s 7,400 MB/s 5,100 MB/s 7,500 MB/s Seq. Write (maximum) 3,100 MB/s 6,500 MB/s 4,700 MB/s 7,000 MB/s Random Read (maximum) 500,000 IOPS (HMB**)
200,000 IOPS (no HMB) 500,000 IOPS 1,200,000 IOPS (HMB?) 900,000 IOPS (HMB?) 1,300,000 IOPS Random write (maximum) 500,000 IOPS 1,200,000 IOPS 900,000 IOPS Enable Chip**HMB = Host Memory Buffer

With a maximum of 5.1/4.7 GB/s, 900,000 IOPS and 1,600 MT/s, the SM2269XT is much more leisurely. A customer is already known here: The Solidigm P41 Plus, as the first client SSD of the new brand behind Intel's former SSD division, will use the SM2269XT and combine it with 144-layer QLC-NAND.

SM2267 and SM2267XT as an entry

One ​​with (SM2267) and one without DRAM (SM2267XT) is available for cheap notebooks provided PCIe 4.0 entry at Silicon Motion. With a maximum of 3.9/3.1 GB/s and 500,000 IOPS, the performance values ​​are only slightly above PCIe 3.0 bolides.

Adata is also a first customer here and presented an SSD with SM2267 almost two years ago with the Gammix S50 Lite.

SMI wants notebooks operate

Apparently, Silicon Motion primarily addresses the notebook segment with all the solutions mentioned, as the following overview by the manufacturer shows:

  • SM2264 Gen4 x 4 lanes, 8 NAND channels up to 16TB (1600MT/s) designed for ultra-high performance & Gaming Notebook PCs
  • SM2268XT Gen4 x 4 Lanes, 4 Channels up to 4TB (3200MT/s) designed for mainstream or high performance Notebook PCs
  • SM2269XT Gen4 x 4 Lanes, 4 Channels up to 4TB (1600MT/s) for mainstream Notebook PCs
  • SM2267/SM2267XT Gen4 x 4 Lanes, 4 Channel up to 4TB (1200MT/s) for value Notebook PCs

The manufacturer is thus avoiding the fight against Phison E18 and Co. in desktop PCs. In this segment, however, the next generation is already around the corner in the form of the Phison E26 with PCIe 5.0, which provides arguments for AMD's new AM5 platform for Ryzen 7000.

Silicon Motion has not yet presented a counterpart in this segment. But the ambitions in the enterprise segment were only recently underlined with the SM8366. With 16 channels and 14 GB/s or 3 million IOPS via PCIe 5.0 x4, it flexes its muscles and is stronger than the competitor's E26, at least on paper.

SSD in E1.S format with SM8366 from the MonTitan platform (Image: Silicon Motion)< /figure>

For the enterprise sector, Phison recently presented its X1 platform together with Seagate. This uses the Phison E20 with PCIe 4.0 x4.