I looked at that too. However, I did a lot of research and felt the Kingston engineers had something special in their design. Remember that there is a custom built controller in these M.2 SSDs (which screw into the PCIe card). That controller is in the little M.2 SSD itself, not on that "carrier" PCIe card. The Predator uses a "next generation" controller that allows use of 4 total PCIe lanes rather than the 2 PCIe lanes that a number of other AHCI controllers are limited to.
I read up on some of the success of two other individuals using exactly this Kingston device on their HP ZX00 series workstations and knew I had a good shot at success. I have read up on other AHCI controller based M.2 SSDs from other vendors such as Samsung where much machinations were needed to get those to work on ASUS motherboards. Those were more recent motherboards than the xw and ZX00 HP motherboards, too. Not something I wanted to deal with, especially knowing of the success of those two other individuals (one in Italy, and the other in this forum).
So, that is why I am only advising this approach at this time. I don't mind dinking around, but not that much......
For others..... you need the little M.2 SSD plus the PCIe card to screw it in to. There are aftermarket PCIe cards you could buy, but I stuck with getting both as a single item from Kingston.