monitor flicker

Hello there i recently got a new PC with a 1660 Super Phoenix from ASUS and i had it for a couple of days but since Monday i think i noticed a Horizontal Black line flash for a second even shorter that couldn't be noticed much but it continued more frequently since then. I have an AOC 27V2Q 27...

I have a serious problem. I have my pc since december and it has a intel pentium g3258 for cpu. The problem is that for some reason it uses a lot of usage even 100% sometimes. For example I can just surf the web and its gonna be 5-20% and it can grow to 70%, and when I open a game or skype it...