U.2 (SFF-8639) Connector Insight When Buying The Intel 750 NVMe SSD

One might have never thought there could be a problem with efficient SSD availability, but many have felt the bite with their Intel 750 Series NVMe SSD purchase. Ordering through online retailers, many bought the newest Intel 750 SSD in what appeared to be a notebook version that connects to PCIe, only to learn that it wasn’t quite that simple.

Intel 750 NVMe SSD RAID 0 X3 Test

To start, retail boxing is very similar with both the U.2 and AIC (Add-in Card) versions, stating ‘PCIe Gen 3 x 4’ which seems to leave both retailers and customers confused. It appears that some buyers were not aware that the 2.5” version of the Intel 750 contained the SFF-8639 connector, a connector now known as the ‘U.2′ to simplify recognition.

SFF Connector

Specific to the Intel 750, the 2.5” form factor also contains a cable that many might think would connect to their computer somehow. It doesn’t. This cable connects to the SFF-8639 connector with a typical PC power connector on one end, only to have a SFF-8643 (mini-SAS) connector on the other end.

Intel 750 NVMe SSDs with U2 Connectors

Ok so… let’s back up a bit and gain a bit of an understanding with respect to why the industry went to the SFF-8639 connector, now known as the U.2. To start, this connector will not fit into a typical PC data connector, regardless of how close it appears to be. SFF-8639 was originally envisioned for the server market where higher performance is paired with the ability to quickly and easily hot swap a drive, similar to the form factor of the Intel 750.

SFF-8639, or U.2, is standardized for NVMe and supports PCIe 3.0 X4, providing five times the speed of a typical SATA SSD. As the Intel 750 is technically aimed at the retail market, why they elected to sell it with the U.2 connector in a retail space with no means of connecting it remains to be seen. Perhaps they have plans that we aren’t quite yet aware of, which wouldn’t be too uncommon for the likes of Intel.

ASRock M2 to U2 Adapter

As if all of this hasn’t been confusing enough, the standard adapter for the U.2 fits into a M.2 connector, also capable of PCIe X4 speeds. Hence, you may start finding U.2 to M.2 adapters as shown above; this is ASRock’s latest. Similarly, we might also see a few motherboard releases with the mini-SAS connector eliminating the need for the adapter.

ASRock U2 SFF Connector in Z170 Extreme 7 Mobo

Understanding the difference between form factors, specifically in the case of the Intel 750, prevents unnecessary return and frustration. Good luck with your Intel 750 NVMe SSD purchase and ensure you make the right selection, be it AIC or U.2.


Stay tuned as we RAID a few Intel 750 U.2 and AIC NVMe SSDs in the next few days for speeds of 5GB/s and over 700K IOPS! Also, check out our Intel 750 SSD Reviews if this SSD interests you!

Check Out Intel 750 SSD Pricing at Amazonblank


  1. blank

    Excellent information.

  2. blank

    does there exist any other U.2 drives than those overpriced intel ones?

  3. blank

    can I connect a mini sas cable to this

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