PC start up problem troubleshooting OS startup

[HeavyHitter]

Hey Guys,

 

I need help with my PC.  I was switching out video cards and now I cannot boot to the OS.  At first I thought it was the video card, but I tested it out on another machine and worked.  I had to remove the main power connector to the board to release the video card, and when I put everything back together I can't get past the HP start up screen.  So I put back the original video card (quadro) back in the machine and still no go.  I hold f11 or esc key but can't get past the following screen after that.  What went wrong?  Did something get fried?  I checked all my connections, everything is secured.  The fans are working, the video card fan is also working, but it just doesn't go any further than the HP screen.  What other things can I trouble shoot?  Please review the pictures if it helps.  Also, if worst case scenario my computer is corrupted,  how do I got about retrieving the data on the SSD?  Thanks so much in advance.