PSU: Slight high pitch whine normal?

[dwluv3333]

Hi guys,

I just built a new computer with a brand new Antec Earthwatts 650. Call me paranoid but I do notice a slight high pitch whine when the computer is off, coming from the PSU. It's only noticeable when I put my ears right next to the back of the PSU, it's definitely not something that is distracting, say, while I'm using the computer or further away from the computer.

So my question is, is this hum normal? My first thought is that it could be, since it is still electrically connected (ready to power on at the press of the power button), but I googled it and have seen that other people's experience with high pitch whining means the PSU is about to die... I just got this yesterday!

Thanks for any confirmation/advice!

 

[Andy2008]

Even though the PSU is nominally off, it is still supplying the +5VSB, i.e. the +5V standby.

Switch-mode power supplies chop up the 50/60Hz mains input into a high frequency, in the tens of kHz range. If it's supplying very little current, that frequency can go lower, into the audible range. Electronic components can physically vibrate at those frequencies, so you can hear them.

It's normal.

Andrew

 

[mindless728]

right next to the PSU, its ok, when you hear it accross you room load, then its a problem