Black Screen on startup

Hi there, I think my GPU is dead! But I am hoping that maybe someone has an idea to fix this issue that I am experiencing. Whenever I turn on my PC it will instantly go to black screen at start up sometimes to a random solid color depending on the app that is showing on my screen. For example...

My PC's gaming performance is pretty bad so I'm thinking about getting a new GPU. I was 100% sure that my CPU's gonna bottleneck while playing games with my new GPU, but it's worth a try asking you guys. I currently have an A10 7800 CPU and an R7 370 GPU I'm thinking about getting a GTX 980 PC...

Hi I just recently had a power outage that turned off my computer while I was on it twice(the first time lights were out for a minute and then the second it was off for 2 hours) When the power came back on for good I noticed that my headphones were not making sound so I tried it on my roommates...