high pitch whine when t43 is on battery

[frdchang]

hello,

i was wondering if there was a definite resolution to the high pitch whine the t43 emits when it is on battery power.

several threads discuss this issue, but there seems to be no definite resolution.

possible causes that were mentioned:
1) lcd light inverter squealing (does not explain why only on battery power the t43 squeals...it would seem that if the lcd inverter squealed, the high pitch whine would be on all the time)

2) some power IC vibrating (i buy this possible cause since it is sort of related to battery power and switch mode supplies do operate at a frequency that can come off as a high pitch whine)

possible solutions mentioned
1) hot glue the perpetuating component to dampen it
2) call ibm and complain and maybe something will happen.


i would like to get this fixed asap since this high pitch whine is noticeable in libraries and such.... i do not wish to bother my neighbors.


cheers,
fred

[christopher_wolf]

Did you try toggling the power scheme settings in the Power Manager? Whenever I hear the faintest indication of a high-pitched noise. Try that first before going to alter the hardware.

[frdchang]

hello,

yeah, i tried toggling the power scheme and it works only a part of the time, but after awhile the high pitch whine comes back.

thanks,
fred

[Initial D]

(this is a repost from me from another thread, but the OP had a different problem)

I wonder if you could try this b/c it seems to work on my laptop if I hear anything similar to that.

If you have Winamp (if not, just download it, it's FREE), just PLAY any music file (doesn't matter if it's a mp3, wav, midi, etc) and press PAUSE. Basically, you're just pressing PLAY then PAUSE. Then MINIMIZE (while it's PAUSED) Winamp to get it out of your face.

For some reason this seems to stop any electrical feedback / static or annoying buzz sound that every now and then comes out to haunt me. I also noticed this worked on my cousin's R32.

Try it and tell me if this works for you...

[frdchang]

i'll try the winamp fix, but i doubt this will fix the problem since the high pitch whine seems to be coming from the power supply within the laptop, not the sound system.

however i am not sure, so i will try anyways just to see.

i am hoping for a definite solution,.... has anyone called ibm and see what they say? if no one has a definite solution, i guess i will call ibm in a week and see what they say.. and if no one on this forum has a definite solution, it doesn't seem like ibm will either.

thanks,
fred

[Initial D]

Actually, on my system, the whine doesn't come from the sound system at all. I think I've traced it to the hard drive at idle state, b/c once the hard drive has any activity, the whine goes away. Once at idle state it'll start coming back, but with the winamp trick it never comes back... tell me if you experience the same... otherwise so far I can only say my t43 and my cousin's r32 have the same unique problem...

[nimativ]

believe it or not opening winamp(or any media player) solves the problem. basically it's something to do with the audio card.

[raabjerg]

Have you tried disabling power management for all USB hubs? (device manager -> for each USB root hub -> properties -> power management -> remove checkmark)

[frdchang]

Have you tried disabling power management for all USB hubs? (device manager -> for each USB root hub -> properties -> power management -> remove checkmark)

i did not try doing this since a previous poster that tried this mentioned that you also lose quite a bit of time on your battery life... but it seems to fix the problem.

i would like to have my normal battery life as well.

[raabjerg]

In my experience the battery loss is minimal - and as you say, often, it does fix the problem.