Computer won't connect to the monitor

Hello! I recently built a pc and it had been running smoothly until I tried overclocking it. Then it had a blue screen and shut down.

At that point I was afraid I broke it as it would not connect to the monitor at all, but would turn on (one of the fans sounded sort of funny.)

But after a few retries, it booted up saying that it had failed entering the system a few times and booted me into safe mode.

Okay, so now its working, and now I had to attach the wireless adapter. I did everything, but there was a connection error so I unplugged the adapter and my computer crashed. Now having the same problem as the overclocking problem, but this time it won't connect to the monitor no matter how many times I retry.

Are there any solutions to this?

Thanks!