90w adapter leads to unusable, jumpy touchpad

[reg1]

strange, on my X220 CI5 unit, when i use the 90W adapter the trackpad is unstable, the arrow on the screen is jumpy and the fan gets louder than when i use the 65W adapter, my 90W adapter is the normal size

So there is a problem . Lenovo says 90W adapter can be used by X220 laptops : ??

[HokieX220]

JamesZ (Lenovo Staff) - you posted on 6/2 that you'd raised the issue to engineering and would keep us posted. How about an update??

[justyn]

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cletus_cassidy wrote:

I can confirm the warbling with the non Ultraslim adapter.  However, in my case, the warbling only occurs when the laptop is running entirely on AC and the battery is not charging.  In other words, I don't hear the warbling when using the adapter and the battery is charging, but I do hear it when the battery is plugged in and not charging or when the battery is not plugged in.

This seems like a power supply issue to me and may be related to the voltage differential you noted.

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Hi cletus_cassidy,

I have created a new thread to discuss this warbling issue:

http://forums.lenovo.com/t5/X-Series-ThinkPad-Laptops/Standard-90w-adapter-causing-warbling-whistlin...

Could you reply to that thread with your 90w adapter model number and what kind of X220 you have, please?

Thanks.

[Mark_Lenovo Administrator]

Hokie,

Engineering is still investigating this and I believe it took a bit of time to confirm this was seen primarily (or only) on P/N 41R4538 adapter.   James may have additional information, but I don't believe we completely understand this yet, so a solution will likely still be some weeks out.

Appreciate your patience on this!

Mark

[jyeah]

Thanks for the update.

I hope the adapter isn't causing undesirable and unrevertable damage to the laptop while a solution is being developed.

[OtherSteve]

That's my primary concern, too, jyeah.

[knife]

I have this problem with my 90W slim power adapter, but only when I am plugged into 240V power (e.g., when traveling in the UK). When plugged into 110, the touchpad is fine with the 90W adapter. Hope that helps track down the issue. I got this computer because I travel a lot, and if I can't use the adapter that is supposedly made for traveling, then there's not much point in having it.

[HokieX220]

I've had the problem using 110 at multiple locations in the US.

[HokieX220]

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Mark_Lenovo wrote:

Hokie,

Engineering is still investigating this and I believe it took a bit of time to confirm this was seen primarily (or only) on P/N 41R4538 adapter.   James may have additional information, but I don't believe we completely understand this yet, so a solution will likely still be some weeks out.

Appreciate your patience on this!

Mark

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 Thanks Mark. Yep, I'm using a 41R4538.  Looking forward to a solution.

[ColonelONeill]

Just like to bump this thread with a Wikipedia article:

"If the computer is powered by an external power supply unit (PSU), the detailed construction of the PSU will influence the virtual ground effect;[citation needed] a touchpad may work properly with one PSU but be jerky or malfunction with another (this does not imply any electrical risk whatsoever, a delicate capacitive ground, not a contact ground, is at issue). This has been known to cause touchpad problems when a manufacturer's PSU, which will have been designed to work with the touchpad, is replaced by a different type. This effect can be checked by touching a metallic part of the computer with the other hand and seeing if operation is restored. In some cases touching the (insulated) power supply with some part of the body, or using the computer on the lap instead of on a desk, while working can restore correct operation."

http://en.wikipedia.org/wiki/Touchpad