NUC 12 i9 M.2 NVMe Questions

[Bill_Murray]

I am ready to order an Intel NUC 12 Extreme i9 edition. I have a couple of questions about the M.2 SSD storage slots. Based on product literature, it appears slots 1 and 2 are located alongside the CPU in the Compute Element, and the third M.2 slot is located on the backside of the Compute Element board.

My questions are:

If all three M.2 slots are populated, is the Slot 3 NVMe card normally the boot and application (program) drive for the system? If not, which slot is the boot/application drive?

Is there a limitation on the size (capacity) for the Slot 3 NVMe card? (I ask this question because one vendor seems to populate that slot with PCIE 3 SSDs, with only one other option for a smaller (512 Gb) NVMe Gen 4 card.)

I am considering a Seagate FireCuda 530 card for the Slot 3 posiiton (if that is the boot drive), either in 1 Tb or 2 Tb capacity. Is there any limitation using either card of this type? I should not choose a card with an installed heatsink, correct?

Thanks for your help.

[n_scott_pearson · Accepted solution]

I will try to answer your questions...

1. Regardless of whether one, two or three M.2 NVMe SSDs are installed, the system drive is whichever drive you select to be the owner for this role. That is, the slot chosen has absolutely no bearing on whether the drive installed in it can (or cannot) be used as the system drive.
2. There are limitations on the physical attributes of the M.2 NVMe SSDs that can be installed in the various slots. The two slots on the 'front' of the Compute Element can accept 22x42 or 22x80 (mm) M.2 Key Type M NVMe or SATA SSDs. The slot on the 'back' of the Compute Element can accept only 22x80 (mm) M.2 Key Type M NVMe SSDs. There is no limitation on the capacity of the SSD drive used in any particular slot. If used with NVMe SSDs (as opposed to SATA), all slots support PCIe Gen4 x4 throughput speeds -- but there is a 'but' that needs to be considered: The slots on the 'front' of the Compute Element provide PCIe Gen4 lanes from the chipset (PCH component). The bandwidth of the DMI bus that connects the processor to the chipset are shared by all of the devices  downstream of the chipset. That is, these PCIe Gen4 x4 lanes share the DMI bus bandwidth with all of the USB, SATA, LAN, WLAN, etc. devices that are downstream. The slot on the 'back' of the Compute Element, on the other hand, utilizes dedicated PCIe Gen4 x4 lanes directly from the processor. It thus should be considered the highest performance slot.
3. Installing the Seagate FireCuda 530 SSD that will be used as the boot/system drive into Slot 3 is a good choice. There is no limitation on the capacity of the SSD used. Bear in mind that it is typically the case that, the larger the capacity of the SSD, the higher the SSD's Write throughput. In the case of the Seagate FireCuda 530 line, the 1TB and higher capacity SSDs all have a theoretical max. read capability of 7300MB/s, but the 1TB SSD has a theoretical max. write capability of 6000MB/s while the 2Tb and 4TB SSDs have a theoretical max. write capability of 6900MB/s (i.e. 15% higher). As for heatsinks, I do not believe there is room for drives with heatsinks; AFAIK, drives with only a heat spreader should be used.

Hope this helps (opinions are my own),

...S

[Bill_Murray]

Thank you for your detailed response! You confirmed what I thought I understood about how the three NVMe slots function and the throughputs that can be expected. I ordered the system and components today and am looking forward to setting up the system. Thanks again for the timely reply.