terrible squealing noise coming from laptop power adapter

expxe · Post by **expxe** » Wed Feb 03, 2010 3:23 pm

any solutions? this only happens when the laptop is off or in sleep mode.

gabeyd · Post by **gabeyd** » Mon Feb 08, 2010 11:29 am

Bump.

My wife's laptop power adapter just started doing this too... Seems to be a new thing.

It is also only when the laptop is sleeping or off.

Anyone figured this out.

andymcca · Post by **andymcca** » Mon Feb 08, 2010 12:29 pm

Does this happen even when the laptop is not connected? Is it definitely from the AC-DC brick? Could be an unhappy capacitor? You could try opening it up and replacing any that look damaged (or all of them), but this will void your warranty and is a risk of electrocution/fire. Make sure you discharge every capacitor prior to doing any work.

Edit:
Found this on some forum, thought it was interesting:

win2kpro wrote:If the high pitched whine is not coming from a fan, then the problem is generally a defective capacitor or capacitors, either motherboard, power supply or video card capacitors.

Years ago I took a mechanics stethescrope and cut and drilled about a 1 1/2" piece of solid plastic dowel to put over the end of the stethescrope metal rod so I could hold it right up against capacitors or the side of fans to locate the source of noise.

If you don't want to invest in a stethescope just take a wooden dowel and hold one end next to your ear, and the other end on the various components.

jessekopelman · Post by **jessekopelman** » Mon Feb 08, 2010 1:47 pm

In my experience, almost all AC-DC bricks squeal. It is really only an issue of how bad. So, in the end the key is trying to keep as much distance and/or stuff between you and the brick. The good part is that most laptop bricks have a pretty long cord.