Some people think the problem around the pcie is related to a bug in the rockchip uboot.
uboot from 2020 seems to fix the problem. I havent tried it.
With the "standard" card you can buy with the rockpro64 i could not see any sata disks but in OMV i got the famous:
ata1: hard resetting link - And the sata card was not visible at all, and i did try almost everything. Nothing postive happened at all.
I was getting tired and did buy a cheap StarTech 2X ESATA + 2X SATA III 6 GB but still with chipset ASMedia - ASM1061 I was surprised it worked. Because everyone was sure the chipset was the fault, i has been told the Marvell 88SE9215 chipset was way better.
I have now been writing on 6TB in a row, no errors yet.
10 DL in progress at same time, with each DL around 8.7 - 9.3 MB/s with the cheap StarTech with chipset ASMedia - ASM1061.
Tested with Armbian image and OMV installed - very pleased with the result.
ROCKPro64 Board ver. 2.0, dated 2018-04-11. Both 2GB and 4GB version.
On these models PCIe 3.3V power is not supplied and the PCIe are therefore not functional.
(Remove R89538 resistor that affects U7109 TCS4484B power regulator, it will supply 3.3V to PCIe bus) - Not tested by myself.
Just to be clear this fix is ONLY for ROCKPro64 Board ver. 2.0, dated 2018-04-11. Both 2GB and 4GB version.