Hi all, my first post on this forum. Not so much a question but rather some possible helpful information regarding the newer style M.2 SSD cards around with regards to the HP Z620 workstation.
I recently purchased a 256GB Samsung SM951 MZHPV256HDGL-00000 PCI Express M.2 hard drive module to install in my HP Z620 workstation, like most people, the transfer speed certainly looks appealing. Prior to installing the module my Z620 was already configured with a 480GB SanDisk Ultra II 2.5" SSD as a boot drive with a Hitachi 2TB ( MBR with 1 partition) 7200rpm second drive and a Seagate 4TB (GPT with 3 partitions) 5900rpm third drive.
I initially purchased what I thought was a generic M.2 SSD to PCIe adapter card on ebay for about £8. (NOTE: These generic cards I mention appear to have the M.2 socket and a power LED with resistors and are very cheap). After fitting the M.2 SSD to the PCIe card, I plugged the card into the PCIe Gen3 x8 lane socket on the Z620 motherboard (i.e. the PCIe slot adjacent to the second GPU slot). Surprise, no SSD visible in the BIOS or under Windows. Like everyone else did a bit of digging around which resulted in me installing a Samsung NVMe driver and trying various other methods found on other forums but without any luck. Still not visible in the BIOS or in Windows.
As a last resort, I thought I would try a different PCIe adapter card and opted for the ASUS Hyper M.2 X4 Mini which cost about £27 on ebay. Swapped my SM951 onto the ASUS PCIe card and plugged it back into the same socket on the motherboard. Switched on the computer and waited for Windows to boot as normal and to my surprise the system appearred to load new drivers for the newly detected hardware. Sure enough, the device was diplayed in the device manager. After initialising the device in Disk Management the device was visible under windows explorer. As a final check I rebooted the PC to BIOS and confirmed the device was diplayed as a legacy bootable device.
Using the same method as I used for installing the OS on the 480GB SanDisk Ultra II, I simply used MiniTool Partition Wizard (which is free) to clone my OS drive to the SM951. (Use the disk copy wizard). After the copying finished my PC rebooted as expected but to my surprise it booted from the SM951 drive. (Note: The PC normally boots to the drive with the new OS but I was surpised that it booted so easily from the PCIe SSD without any tweaking). To confirm the changes I removed the 480GB SSD and tried rebooting which it did without any problems. After running Crystal Disk Mark 5, I can confirm read speeds just above 2000MB/s and write speeds of about 1300MB/s. My SanDisk SSD (which is one of the better SSD's on the market) reached about 550MB/s read and about 500MB/s write.
In summary, it appears the PCIe adapter card seems to be rather inportant if you want to use an SM951 M.2 SSD I would recommend you avoid the cheap adapter cards on ebay.
Although I cannot say for certain, using the ASUS adapter card may allow the SM951 to work as a bootable drive on the older Z400/Z600 machines since it dispays the SSD as a legacy device in the BIOS.
My full system:
2x Xeon E5-2670, 64GB (8x 8GB) 1866MHz RAM, Samsung SM951 boot drive (via ASUS Hyper M.2 X4 Mini Adapter), SanDisk 480GB SSD, Hitachi 7200rpm 2TB, Seagate 5900rpm 4TB, Syba 2-port SATA III with 2x USB3.0, Quadro K4200, Tesla M2090, ICY Dock hot swappable 2.5" and 3.5" drive bay.