ADT-Link’s enclosed U.2 adapter sustains nearly 8GB/s without thermal throttling

The R27A-BK3 turns a standard PCIe slot into a high-speed U.2 connection, with active cooling helping Gen3 and Gen5 drives maintain sustained performance.

ADT-Link’s R27A-BK3 is a low-cost way to mount a U.2 NVMe SSD in a system that only offers standard PCIe slots. In practice, it is a large, enclosed adapter built around a full-length drive bay, a blower fan and the conversion board itself. ServeTheHome noted that the metal casing does more than provide protection: it also helps direct airflow across the drive, which matters because the SSD sits inside a closed shell rather than in open air.

The key detail is compatibility. ADT-Link uses the R27A designation for U.2 drives with an SFF-8639 connector, while its EDSFF products use a different model number and a different connector standard. That distinction is easy to miss, and it is the main source of confusion for buyers. ADT-Link’s own product information lists the R27A as a PCIe 5.0/4.0 x4 adapter for U.2 drives, and says the range also includes separate variants for U.3 and EDSFF devices. The upshot is simple: this model is not a general-purpose SSD adapter, and choosing the wrong version will leave the drive physically incompatible with the card.

Performance in testing was solid across both older and newer drives. ServeTheHome first ran a Samsung 7.68TB PCIe Gen3 x4 U.2 SSD, which reached 2,252MB/s and then settled at 2,179MB/s over a 20-minute run, with peak temperature at 78C. It then tested a Solidigm D7-PS1010 7.68TB PCIe Gen5 x4 drive under a sustained sequential write workload, where throughput peaked at 7,946MB/s and held at 7,838MB/s, with temperature topping out at 70C. In both cases, the drives remained below their warning thresholds and the site reported no sustained thermal throttling.

That cooling result is notable because earlier testing of the related EDSFF version of the same family suggested the platform could behave differently depending on the drive type fitted. In this U.2 variant, the fan and enclosure appear to provide enough thermal headroom for sustained use, at least in the conditions tested. For workstation, server and homelab users who need to repurpose a U.2 SSD without a native U.2 backplane, the R27A-BK3 looks like a practical if fairly specialised option. The main caveat is still the same one ServeTheHome and ADT-Link both stress: verify the exact model before buying.