Grey Screen

so when ever i go into a match of League.. and roughly 3 mins to 6 mins in. the Grey screening Starts. and it does it randomly from 30 secs to 2 mins roughly. ive been dealing with this for a while now. and ive thought it was my computer at first and i looked it over. ( its not even 6 months old. new built my Self. ) so anyways i get into team fights my Screen goes grey, then black and then shows the game and while this is all happening i hear my Sounds as if normal. i did not have this happen to me a year ago with a GAMING LAPTOP. its getting worse. NO OTHER GAME DOES THIS and i run them on all Ultra+ Wow, any of my steam games, fornite. i thought i was my Screen. i changed screens. nope still does it.. i thought it was my graphics Card. nope fixed it too, took it off my mother board and re checked all the connections. and even put a Brace on it to make sure it doesnt Bend.

Now i love league and i dont want to quit becuase of this ONE ISSUSE i have. i just want to play League with out being intantly ragefull when i see that Grey/black Screen. i have no idea what to do anymore. i have tried the trouble shooting, reinstalling and completly deleting it. and it Still has not fixed what EVER issuse it it.

please... just fix it