(PCI_E2 supports up to x16 speed, PCI_E4 supports up to x4 speed)
While you know the other slot works, it looks to not be for video cards.
I recently switched my Graphics Card from one PCI slot to another (I know the slot I switched it too works). But when I booted up my PC, it cannot recognize the card. The fans are spinning, and my monitor works (the monitor is connected to the GPU), but when I load a game or anything graphic wise it just slows down to about 1FPS and sometimes lower. I tried updating my drivers for the card but when I go to device manager I cant find any settings remotely related to Graphics. So I'm about to take a screenshot to post here, when all of a sudden the screen flickers black and then back again. I suddenly hoped that the graphics card was back, and it was... I have no idea what happened but it's working now. Could someone explain to me what just happened?
NVIDIA GeForce GTX 950
MSI 970A-45 Motherboard