LCD gives irritating high-frequency sound !

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Can anyone tell me what electronic component I should replace if a
computer 17" LCD-monitor gives a irritating high-frequency sound? I'm
not a genius in electronic but I can solder and maybe repair a 4years
old teriffic lcd screen.

Also I like to know if a LCD has also the dangerous hi-voltages like
the old TV's?

Samsung SyncMaster 171N

Thanks you!

 

[Meat Plow]

Can anyone tell me what electronic component I should replace if a
computer 17" LCD-monitor gives a irritating high-frequency sound? I'm
not a genius in electronic but I can solder and maybe repair a 4years
old teriffic lcd screen.

Also I like to know if a LCD has also the dangerous hi-voltages like
the old TV's?

Samsung SyncMaster 171N

Thanks you!

Probably the SPMS. Takes more than soldering skill to troubleshoot those
and they do have some lethal voltages.

 

[Meat Plow]

Probably the SPMS. Takes more than soldering skill to troubleshoot those
and they do have some lethal voltages.

errrp SMPS

 

[[email protected]]

Probably the SPMS. Takes more than soldering skill to troubleshoot those

and they do have some lethal voltages.

thanks, but what is the SPMS and how does it look like?

Also how can I safely remove the high voltages without damage the
electronics or me

 

[PhattyMo]

thanks, but what is the SPMS and how does it look like?

Also how can I safely remove the high voltages without damage the
electronics or me

The SMPS is a "Switch Mode Power Supply",it may be "internal" to the
monitor,or it might be in the little "power pack" for it (varies by
model.My monitor has it internal -no "power pack".)

You can generally tell the SMPS section by the small ferrite
transformer,and a large capacitor (400V,100uf,perhaps.) *Discharge that
capacitor before you even think about poking around inside!* (don't
short it out though!)
High voltage hurts,at the least..and worst case,can be !LETHAL!

Another possibility is the CCFL inverter for the backlight.
Again,High voltage on the output side (the side that goes to the
backlight tube(s).) There is likely a small 2KV 100-1000PF capacitor in
series with the lamp(s)..you might want to discharge it also (short it
with a screwdriver -DO NOT use this trick on larger caps -big BANG,and
lots of sparks!)

Those are about the only possible sources of 'whine' in an LCD
monitor,that I'm aware of.