I have Rampage V Extreme and X99e-WS-3.1 motherboards.I have i7-5820K I7-5960K i7-6850K and Xeon E5-2697AV4 CPUsWith the I7-5280K all PCI-E slots work.With other three only the three slots closest to the CPU work.Am I missing a setting in BIOS or ...

Mother board is a Rampage V Extreme latest BIOSI have two CPUs a I7-5280K and a I7-5960xAll slots work with the 28 lane 5280k but the lower slots dont work with the 40 lane 5960xIs there a setting I need to make in BIOSNot using the m2 slot