Is this Me or Is this happening to everyone else

For a while now, I couldnt play rank for a while because my computer hates rank ... It crashes every 1/ 45 games ( Yes i keep track) but Today i was playing rank and during a team fight , a AFK Popup appear making me unable to participate in in the game and i had to exit the game . I hurried and tried to join the game back again and i got another pop up and had to leave game again . Once i joined the game again my team already lost and blamed me for it , And to make matters worse I've been placed in the Low- Priority Queue Due to "AFK". Its been a while since i afk , The last time i afk'd was in Sept. So for me to be placed in LPQ for something i didn't do or cause is ridiculous. What is the Difference between Rank and Normal and Why do i only Crash in Rank ? Justice Please ?