Hi, I have an ASUS z270e with a GTX 1060 6GB, and the GPU is not detected at all anywhere when it is in the 16x/8x slot when I put it in the 8x slot it works fine though. There is no sign of damage to the 16x slot. Previously it worked fine, and two GPUs were put in it, one in the 16x slot and one in the 8x slot, but they didn't support/have an SLI connection, so maybe the 16x slot was somehow disabled, I've searched the settings, updated the uefi bios, reset the cmos multiple times, but to no avail. It has an intel i7-7700k, which I removed and checked, and it appears fine, and I have 2 Sata SSDs connected.
Any help would be appreciated, it works fine for the moment in the 8x slot, but in the future I may want a second GPU or one that really needs 16x PCIe.