Question My computer decided to act strange for some time, not sure what that means

[Polytonic]

Sooo... Where do I start?

Well, I was just playing for a few hours and suddenly, out of nowhere the game crashed. After that the HDD got really noisy and then I couldn't even move my mouse for a bit, then my screen artifacted for a few seconds and blacked out. About 7 seconds later my primary monitor turned on and over time the windows user interface elements and explorer reloaded for some reason. Then it was all good, I am literally writing this with my own computer now, but my second monitor, which is connected to the integrated graphics does this: I turn it on, it shows a black screen for 6 seconds, then it says "NO VIDEO INPUT". This is as much as I can tell.
By the way after everything "got back to place" an artifact appeared near my mouse cursor for a split second.

Does anyone have a clue what does this mean?

Hardware Info:
Intel Core i5-2400S
GeForce GT 1030 (GDDR5 Low Profile) [Connected to primary monitor]
Intel HD Graphics 4000 [Connected to secondary monitor]
Hitachi 1TB 7200RPM HDD (System drive)
4 sticks of 2GB DDR3 RAM (8GB)
Nothing overclocked, nothing messed around with.

Operating System: Windows 10 Pro
Manufacturer: HP

 

[Polytonic]

Btw I'd like my secondary monitor to do what it should do instead of not detecting video input.