Monitor Causes Power Supply to Buzz

By ryboto ยท 6 replies
Jun 1, 2006
  1. Ever since I've owned my Acer AL2032WA(i think that's the model, it's a 20'' widescreen), whenever I power it on, i hear an electrical buzz in my power supply. I've even tried plugging the monitor and power supply's on two separate Monster Power surge surpressors/noise reducers, but, the buzz is still there for the first minute that the monitor is on. Oddly, this even occurs when the pc is off/power supply switch is off. The only conclusion I can think of, is that the monitor is causing either EM interference, or it's sending noise into the computer via the DVI cable...

    My noisetaker psu just died abruptly for no reason, and the old whisper series I'm using until I get an RMA experiences the same buzzing that the noisetaker did. Since I've owned the monitor, I've owned used two different video cards, and two different motherboards with it, and in both combinations, i hear a buzz when i first turn the monitor on, or when it comes out of standby...

    could this be hurting my psu?
  2. Nodsu

    Nodsu TS Rookie Posts: 5,837   +6

    Some CRTs degauss themselves every time they turn on. So yes, it is probably the degaussing circuits inducing or emitting some noise.

    See if you get the buzz with the DVI cable unplugged. If it still buzzes, then the cause is EM radiation and it's nothing to worry about.
  3. ryboto

    ryboto TS Rookie Topic Starter Posts: 34

    do LCD's degauss? I forgot to mention, that it's an LCD monitor..
  4. Nodsu

    Nodsu TS Rookie Posts: 5,837   +6

    With an LCD, I'd guess it is the backlight turning on that is causing the noise..

    If the monitor is still under warranty, then you should have it looked at.
  5. ryboto

    ryboto TS Rookie Topic Starter Posts: 34

    I'll have to pay shipping to have it looked at...the noise is even present if i keep the DVI cable, even with no physical connection to the psu, the monitor causes it to buzz.
  6. Nodsu

    Nodsu TS Rookie Posts: 5,837   +6

    Well, radiated EMI will not damage any of your equipment. You may have even seen these FCC labels: "this device must accept any interference.."

    Still, the backlight startup generating so much noise does suggest poor design or bad components.
  7. CrossFire851

    CrossFire851 TS Rookie Posts: 766

    That would be be FCC part 15 (1,2).
Topic Status:
Not open for further replies.

Similar Topics

Add your comment to this article

You need to be a member to leave a comment. Join thousands of tech enthusiasts and participate.
TechSpot Account You may also...