Hopefully, this is going to be something simple. I tried to replace my airport card today as Mojave won't see the current airport card that is in my mac pro. I bought a card on eBay and started what I hoped would be an easy project. I had a hard time getting one of the screws out that held the card down and it was so stripped I had to pull the card out. The piece holding the screw came off but I don't think that's a huge problem. I got the new card in and connected the antennas Now my Mac Pro will power on white light" but nothing displays on the screen. I don't hear a startup chime and it just sits there with the light on. I tried booting it with no Wifi Card in and plugged into ethernet and i even tried installing the old card. I assumed it might be something simple so i made sure my video card was pushed in all the way and the trey with the processor with the RAM is going in smoothly. But nothing has helped. The only thing I can think is when I was pulling on the antenna wires something else may have come loose. Any help or ideas would be greatly appreciated.