Like many of you guys, getting super frustrated with this. First PCIE Riser would only work in second PCIE slot at 2.0 - Received a replacement but now the top slot works but only runs at x4 speeds as opposed to the x16 that it should run at. Anyone else having a similar issue? Have checked BIOS etc, tried when GPU under load and just can't get past it. Surely I can't be this unlucky to get TWO dud PCIE risers in a row...