Intel’s “ruler” form factor for NVMe server SSDs once looked radical, but it’s now become mainstream. As evidence, Samsung just introduced a new line of ultra-fast PCIe Gen 4 drives derived from Intel’s original design. The PM9A3 SSDs come not only in the standard M.2 NVMe format, but also in the newfangled E1.S format (a shorter version of Intel’s ruler) and U.2 — which looks like a SATA drive but is much, much faster.
The E1.S and U.2 variants of these drives (designed for data centers, not consumers) can hit up to 6,500 MB/s read and 3,500 MB/s write speeds and capable of 900,000 IOPS (random reads). These speeds are double what PCIe 3.0 drives can handle because PCIe 4.0 has double the bandwidth. The M.2 version of the PM9A3, by contrast, can “only” run at 3,500/1,750 MB/s.