my MacPro5,1 SSD upgrade conundrum
I'm looking for some advice on SSD upgrade for MacPro4,1->5,1 w/ 2 x 3.46 GHz 6-Core Xeon x5690, 32GB memory, SAPPHIRE Pulse Radeon RX 580 8GB graphics card, Sonnet Tempo SSD PCIe w/ 1TB Samsung 860 EVO, macOS 12.6 boot and scratch, macOS 10.13.6 on 500GB Samsung 850 EVO, and 6 disk Raid1+0 User Volume, plus two external enclosures for TimeMachine, CCC, and RAID5 working storage one eSata and one USB3. I have one empty PCIe slot, I could use slot 2 or 3.
This is being driven by some feeling of sluggishness and having to deal with HDD replacement. My 1TB boot SSD is not large enough for my User directory tree (photos and music exceed 1TB). I am thinking a 4TB SSD would allow me to abandon my somewhat troublesome internal/external User Raid1+0 volume freeing up SATA bays for 14+TB drives for TimeMachine and CCC and relegating external storage for secondary backups and non active storage.
For SATA SSD's thinking of either 4TB Samsung 870 QVO (don't like warranty) or 4tb Samsung 870 EVO. My primary reservation is that I expect I will upgrade to Apple Silicon MacPro during the next couple of years at which point current SATA SSDs would presumably feel way too slow. In looking at Post #1's NVME drives its only the Sabrent Rocket which seems to offer an affordable 4TB solution.
If I was to leave my current boot volume and just focus on a faster User volume would other lower cost 4TB NVME drives such as Crucial P3, WD, Seagate, Kingston be useable, or do they have issues beyond being used a boot volumes?
Should I just go with SATA and stop thinking that current NVME might be better suited to future hardware?
If it's feeling sluggish, you might want to put your two installs (12.6 + 10.13.6) on NVMe drives on an x8 or x16 card with a PCIe switch in slot 2. then you can put your user volume on 2.5" SSDs on the sonnet tempo card. It would be the fastest setup, but involves spending more money.
That said, could you not move the 6 SATA drives from your RAID 1+0 array to the 6 internal SATA slots in the cMP (4 trays + 2 in optical bay)? That configuration would give u room for 6x SATA II HDD, 2x SATA III SSD, and 2x/4x NVMe SSD (depending on which PCIe switch card u get).
You could even downsize to a 4 drive RAID 1+0 array in the trays and use the two optical bay SATA slots for Time Machine and CCC backups. But even if you opt out of NVMe, moving the array of SATA HDDs to be completely internal seems like it would clean things up a bit. USB 3 can be a bit of a bottleneck, even with the ideal card. Even with eSATA, i imagine the internal backplane would be more efficient than a PCIe card that has to share the PCIe bus with everything else you have plugged in.