#11092 LOW Not Tri: Some XO 1.75s may have noticable power supply whines on XO-1 charger

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#11092: Some XO 1.75s may have noticable power supply whines on XO-1 charger
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 Reporter:  greenfeld    |                 Owner:  wad        
     Type:  enhancement  |                Status:  new        
 Priority:  low          |             Milestone:  Not Triaged
Component:  hardware     |               Version:  1.75-B1    
 Keywords:               |           Next_action:  never set  
 Verified:  0            |   Deployment_affected:             
Blockedby:               |              Blocking:             
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 XO 1.75 B1s may have noticeable internal power supply whines when used
 with a green XO-1 wallwart charger, even with a fully charged battery.
 The two I was given exhibit this behaviour.

 SHC12900064 in particular was making a high-pitched whine in such a
 situation which seems to vary in tone based on CPU or other activity
 usage.  The other one I have is at a lower tone and much quieter when used
 with a Green XO-1 wallwart supply.

 We have one XO-1.5 which acts like this on an XO-1 charger, but I think
 the rest seem fine.

 If this is indeed an actual problem we should try and mitigate this,
 presuming XO-1 style chargers are acceptable for use with 1.75's.

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Ticket URL: <http://dev.laptop.org/ticket/11092>
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