PCIe3 NVMe - Cable length, # Connections - Retimer?

[UhClem]

Host: Dell T30 ; E3-1225v5 x16 slot (cpu lanes)
Target: SK Hynix P31 1TB NVMe

Long:
1. PCIe_x4-M.2
2. M.2-SFF8643 (red)
3. SFF8643-SFF8639 cable 50cm
4. U.2-M.2 case
5. M.2-PCIe_x4 riser (white)
6. PCIe_x4-M.2
7. M.2-SFF8643 (red)
8. SFF8643-SFF8639 cable 50cm
9. U.2-M.2 case
10. SK Hynix P31 1TB NVMe

Short:
1. PCIe_x4-M.2
2. SK Hynix P31 1TB NVMe


Long:

~/bin [ 1060 ] # for i in {1..5}
> do
> xft -b16m -D3 -s100g -uMudbo /dev/nvme0n1
> done
/dev/nvme0n1: 3489.6 Md/sec
/dev/nvme0n1: 3489.8 Md/sec
/dev/nvme0n1: 3491.5 Md/sec
/dev/nvme0n1: 3492.0 Md/sec
/dev/nvme0n1: 3493.6 Md/sec
~/bin [ 1061 ] # for i in {1..5}
> do
> skt nvme0n1p43 128
> done
485200 ops/sec
492856 ops/sec
492416 ops/sec
506112 ops/sec
509416 ops/sec
~/bin [ 1062 ] #

Short:

~ [ 998 ] # for i in {1..5}
> do
> xft -b16m -D3 -s100g -uMudbo /dev/nvme0n1
> done
/dev/nvme0n1: 3491.2 Md/sec
/dev/nvme0n1: 3492.3 Md/sec
/dev/nvme0n1: 3491.1 Md/sec
/dev/nvme0n1: 3504.9 Md/sec
/dev/nvme0n1: 3490.0 Md/sec
~ [ 999 ] # for i in {1..5}
> do
> skt nvme0n1p43 128
> done
491632 ops/sec
499192 ops/sec
504888 ops/sec
503936 ops/sec
501816 ops/sec
~ [ 1000 ] #

============
(from "Treasure of the Sierra Madre" et al)
"Badges? Retimers? ..."