Question HP Probook 4710s powers on but no display ?

[mitk0o0o0]

Hello. I've got an old HP Probook 4710s and it suddenly stopped working. When I power it on the fan starts spinning, I can hear the DVD drive move, and the display's backlight turns on but nothing is happening.

Here's the stuff I tried:

• Removing battery, holding power button for 15-30 seconds
• Connecting to an external monitor
• Reseating the RAM, trying them out 1 by 1 on different slots
• Removing keyboard
• Removing touchpad
• Removing the hard drive
• Removing the CMOS battery
• Removing the video cable for the display and putting it back

At this point I've run out of ideas to try and its leading me to the conclusion that something inside is toast. CPU, GPU or motherboard maybe? If it turns out to be some corrupted BIOS would I be able to restore it? Does anybody know what else I could try? I've also uploaded 2 pictures. Is the other LED on the bottom supposed to be blinking? I think the right one is power/charging indicator but what about the left one?

 

[mitk0o0o0]

So after unplugging the display cable and powering it on it seems to boot. The hard drive starts up as well which previously didn't seem to and that left side LED begins blinking. Then when I connect a VGA or HDMI cable I can see the screen. For some reason I was getting a BSOD because of a bad video driver so I uninstalled it and it boots but only as long as the display cable inside is disconnected it is able to start up and I am able to see an image on external display. How can its screen be causing these issues?

EDIT: Almost forgot to mention, when connected to an external monitor there are these red stripes. Faulty GPU?

BSOD after Windows automatically updates the video driver