SXPS1645/7 Another Power Brick Issue

I would like to bring this to attention for the community, as it recently happened to my SXPS1647. This happens with the 90w brick and only on certain firmwares. The proc in my system is the core i7 620m.

One night just before bed i closed the lid on my laptop to put it to sleep and then turned off the TV, but then i heard a strange high pitched sound coming from the laptop area. I went back and investigated and there was a strange sound coming from the power brick. The best way I can describe it is the sound of electricity moving, a wave like sound that gets higher and lower pitched. Very concerning, so I call Dell and tell them the problem they send a new motherboard and ac adapter.

The dell tech comes to my house and says that's the strangest thing he has ever seen/heard. So he tries the new ac adapter and same sound so he replaces the mobo. With the new mobo the sound is not present, so im happy. But the computer was throttling really bad so i decided to check the bios with CPUZ and it was A01. I decide to update the bios to get rid of the throttling issues, A05 update went nicely but as soon as I restart the system the magic high pitch sound has returned. The previous mobo had the A04 bios when it was making the sound.

I recently read the whole 90w vs 130w ac adapter and wonder if that has anything to do with this issue?

I wanted to raise this issue to see if anyone else has heard this sound coming from their adapter. I heard mine from about 4-6 ft away but it can be clearly heard when you press your ear to the brick, or even hold it close to your ear.

 

I know the sound you're talking about, and the only times I ever heard it was when my brick was about to die. It makes that sound for a couple of days (in my case) before it dies. Pluggins and unplugging helps the process and makes it die quicker...

It might be something else in your case, but that's my experience with three bricks on three different laptops (all Dell).

 

mourningstar62,

Contact Dell and let them know that you need a 130 Watt Adapter.

Refer them to this post:
http://en.community.dell.com/forums/t/19320784.aspx

Good Luck.

 

Thanks mitchell, but isnt it strange that the bios update caused the sound. Before the update there was no sound at all.

@danp I have contacted them and a 130w adapter is on its way

 

The BIOS updates made changes to the throttling, which would affect the power draw.

I don't recall all the details, but maybe the A01 BIOS limits the draw to 75W, while the later BIOS increased the max draw enough to stress the 90W adapter. Stress leads to funny noises and death...

 

Let us know how that 130 works out.

Good Luck.

 

I experienced the same noise with the factory 90w slim adapter and also the adapter became extremely hot. After contacting tech support, they replaced it with a new 90w adapter which resolved the issues, which again was replaced by tech support by a 130w brick to solve cpu throttling

 

Hey everyone, I just got my new 130w power adapter and tried it out. Now there is just a little noise coming from the bottom of the adapter from the end where it goes to the laptop.

While charging the noise is faint but still sounds terrible. When I close the lid with it on and putting it "sleep" mode the noise gets higher pitched and you can hear it from about the middle of the adapter instead of just the far bottom of the adapter. When shut down the adapter makes about the same noise as it does charging.

I would urge everyone with these laptops to check out their power brick see if this a more widespread problem.

As for my personal situation what would be the next step? I have thought about a system swap, but i cant really justify it when there are no other problems with the computer.

 

After 10 minutes and the adapter warmed up the noise got louder during all areas of operation. including sleep and turned off.

 

After a day with the adapter, I notice the noise is more noticeable while charging and when its idle its still there but not as bad. The sound coming from this one is different than the 90w one it sounds more like static coming from an old CRT television than an electric current.

 

anyone think its a problem now with the little sound coming from the brick? Its def not as bad as the 90w one