kp99

Hi there, and thanks in advance. My year-old PC has, over the past few days, begun to make a worrying buzzing sound when I turn it on. The noise continues indefinitely until I switch it off – but usually disappears if I turn it on again a few seconds later. After that, the computer works completely normally (including, it seems so far, for high-intensity processes like gaming), and subsequent restarts cause no such problem. But as soon as I wait a few hours (or overnight), the problem occurs again. I’ve opened the case while the buzzing was happening but couldn’t isolate where the noise was coming from. Any ideas what the problem might be? I suspect it may be a fan or hard drive – but that's just an uninformed guess, really. Other than the noise, the computer seems to have no problems and restarting on start-up is only a minor inconvenience. But I’m concerned that this might underlie a more damaging problem. Any help would be greatly appreciated.