Faulty Computer

Remember I wrote earlier that there is something wrong with my PC, where it would take 2 hours for my PC to start up? For 3 days, I had to wake up at 5am to turn on my PC so that I can start using my PC at 7am. I thought there was something wrong with the connection of the CAT5e cable or the CPU but on the 4th day, the problem was resolved by itself. However, the monitor would be shaky and vibrate once in a while. I better get the computer guy to bring my CPU to his shop to have it investigated before something really major happens.