P170HM turns on but black screen

Yesterday I was using my laptop and closed the lid which caused Win10 to hibernate. No problem, do it all the time. When I came back about 30 minutes later to use it again, the laptop turned on but the screen was completely black. Tried hitting Fn+F7 and all the other keys which affect display but nothing. Tried a hard reset but nothing came up on boot up, not even post.

I took off the bottom and noticed that the heatsink fins were completely caked with dust. I'm thinking the GPU...

P170HM turns on but black screen