This is good advice. I had an issue like this with a Capture Card. It was the correct x4 slot but didn't work. How to know then so I don't find out the hard way?Oaktown wrote: ↑Tue Nov 21, 2017 17:07What kind of motherboard/CPU do you have? Your black monitor issue could also come from the fact that you don't have enough PCIe bandwidth to support 3 P4000 GPUs. These cards are PCI Express 3.0 x16 but they will also work at x8 so if you have three I think you'd need a minimum of 32 lanes available (x16 for the main and x8 for the second and third card) to be able to use them properly.
Also keep in mind that not all PCIe slots are created equal so just because it can take a x16 card doesn't mean it can run at x16 or even x8 sometimes a x16 slot will run at x1 or x4.
Just check the PCIe lane assignment in the manual for your motherboard and you'll find all the information you want.