PCIe and PCIe - Difference between x8 and x16

What is the maximum read and write speed for pcie x4 slots? pcie 3 slot 1 x PCIe x16 slot Intel® Z790 Chipset 3 x PCIe x16 slots 1 x PCIe x1 slot so there is not a 2nd pcie slot at x8 Originally pcie 4 ssd in pcie 3 slot I believe both slots are generation 3 because chapter 1 of the manual indicates that HP only offered Gen 3 NVMe SSD's in the model series and

pcie training error slot 1 Riser with Three PCIe Gen3 slots 1 x16 FH 1 x8 FH and 1 x8 LP at least 2 processors R740XD CusKit The Riser from Dell™ fits into