cMP 4,1 PCIe Slot2 bug

Long story short, I've read it mentioned somewhere that a bug exists with PCIe slot 2 (which is x16) where it only works at half the speed on cMP 4,1 (maybe 5,1 also). I've done fairly exhaustive searches and can't find anything specific about this and whether there is a solution to the problem.

I experienced this bug myself when I installed my Samsung 960 EVO 500GB M.2 NVMe into PCI slot 2 and only got half the speed for read/writes that I got when it was installed in slots 3 and 4 (read...

cMP 4,1 PCIe Slot2 bug