UNIS, a subsidiary of Tsinghua Unigroup, has introduced its S5 series of PCIe 5.0 SSDs, presenting a formidable alternative in the high-speed storage market. The S5 lineup claims to achieve impressive speeds of up to 14.9 GB/s, surpassing key competitors such as the Crucial T705 and Samsung 9100 Pro, both of which are already recognized for their rapid performance.
UNIS S5 Ultra and S5 PCIe 5.0 SSD Specifications
The S5 series consists of the standard S5 and the enhanced S5 Ultra, both designed in the M.2 2280 form factor with a PCIe 5.0 x4 interface. Following their launch in China, these drives are expected to be available on Western platforms like AliExpress for further evaluation.
| Name | UNIS S5 Ultra | Samsung 9100 Pro | Crucial T705 | UNIS S5 |
|---|---|---|---|---|
| Flash Memory | TLC NAND | 236-Layer Samsung TLC NAND | 232-Layer Micron TLC NAND | TLC NAND |
| Form Factor | M.2 2280 | M.2 2280 | M.2 2280 | M.2 2280 |
| Controller | Unnamed 6nm-based controller | Samsung Proprietary (Presto) | Phison E26 | Unnamed 12nm-based controller |
| DRAM | Yes | Yes | Yes | No |
| Sequential Reads | 14.2 GB/s | 14.8 GB/s | 14.5 GB/s | 14.9 GB/s |
| Sequential Writes | 13.4 GB/s | 13.4 GB/s | 12.7 GB/s | 12.9 GB/s |
| Random Reads | 1,700K IOPS | 2,200K IOPS | 1,550K IOPS | 1,800K IOPS |
| Random Writes | 1,600K IOPS | 2,600K IOPS | 1,800K IOPS | 1,700K IOPS |
The UNIS S5 boasts sequential read and write speeds of 14.9 GB/s and 12.9 GB/s, enabling it to outperform most competitors in its class. Additionally, the S5 offers random read and write rates of 1,800K IOPS and 1,700K IOPS, respectively. Notably, it operates with a less advanced unnamed 12nm controller and lacks DRAM, a design choice that could be limiting for some users.
In contrast, the S5 Ultra utilizes a dual-PCB structure and incorporates a DRAM cache, enhancing its overall performance. It features a 6nm controller, likely based on Silicon Motion technology, and delivers slightly lower sequential read and write speeds of 14.2 GB/s and 13.4 GB/s. Random IOPS for the S5 Ultra are also lower at 1,700K and 1,600K for reads and writes, respectively. This model is available in 2TB and 4TB configurations, which could be a drawback for budget-conscious consumers.
While the S5 Ultra may seem slower, its DRAM cache is advantageous for productivity-focused systems. Both models are designed with a 1mm graphene passive heat sink, although better cooling solutions would be beneficial considering the high-speed capabilities. As these SSDs prepare to enter the e-commerce market in China, their actual performance will require independent testing for verification, as manufacturer claims often lack objectivity.