This RockPi 4 looks to be one of my worst purchasing decisions of all time. The designers must have been on drugs - for instance, you cannot get to the eMMC without removing the heatsink first.
Other things that you take for granted - like the TTY being correctly sized to your monitor on boot - are broken on the RockPi 4. It opens the TTYs to what looks like about 640x480 on a 1920x1080 monitor. I have to install the fbset command to fix it, and that has to be done on every TTY. Also the boot menu does not show, so there is no way to choose kernel. I am using extlinux on the Ubuntu Server image.
What is worse is that the onboard devices such as USB and the GPU are “magically” connected - they do not appear on the PCI busses. This is horrible for configuration and development purposes.
Anyway, the question I have is the following:
If I use a Samsung 950 Pro SSD, I only get 600MB/s, which is very slow for PCIe 2.0 x4. Looking into the configuration, it appears that it is only running at 2.5GT/s. How do I get it to work at 5.0GT/s?
It does not matter if I use the ribbon cable or shove the SSD straight in the board, sticking out of the side.