Thinkpads Forum

Hello,

First of all, sorry for my bad English

I am Lenovo ThinkPad T430 user. I have eyestrain after short time of using this laptop ONLY when it is connected to AC Power. I can notice minimal change of the displayed image when AC Power is connected/disconnected - different brightness, contrast, refresh rate(it is hard to recognize and describe it - just different ) on AC power. It makes my eyes feel uncomfortable and all on the screen little harder to read/look after short time of using laptop. By accident, i discovered, that when I'm disconnecting Power Supply, this feeling pass away and I can use the screen without problems. But of course I can't use my laptop all the time on battery power.

I tried:

- External Monitor
- Windows / Linux on various drivers and various configurations (I can notice it even for example during booting system installation)
- Other Power Supply (both of them 90W version, i don't have any 65W to try)
- Laptop Display exchange

In all cases same symptoms.

Where else the problem can exist? Is it really possible to change displayed image becasue of AC power usage , regardless of OS and drivers ?

I know that it sounds really strange, but it is true (and really really big problem for me because it is my work notebook).

Thank you for your help in advance

Greetings

Had tried different power supply yet?

Cheers, thinkpadcollection.

As i told, i tried different power supply, same effect ;/

I am operating under the assumption that you have Windows Vista or higher.

Have you tried looking at the Lenovo Power Manager (if you have it) or the Windows power options under the Control Panel? You can change the brightness settings under each individual profile for both Lenovo Power Manager and Windows power options.

There's always the option of pressing Fn + F8 to lower the brightness so that you can adjust to a comfortable setting.

Probably it's PWM dimming related; rise the brightness at 100% and see if it's better, and then try various brightness levels.

@AIX

I tried ;/ same effect on 100% brightness (only on AC power enabled). I tried all brightness levels - everyone is bad on AC power and fine on battery power.

That's strange...

Another thing, I think there is a BIOS setting regarding display's brightness, try to change it, maybe it's worth a shot.

It may be your LCD's refresh rate.
Check this similar stuff:
http://www.thinkpads.com/forum/viewtopic.php?t=92540
https://forums.lenovo.com/t5/ThinkPad-T ... a-p/461845
http://forum.notebookreview.com/threads ... ff.694732/

Hi, sorry to hear about your problem. My 2 grosz: it could be cool to somehow confirm it objectively. So that we know it's more than the effect you perceive. If I'm not wrong, someone here (ibthink?) works at notebookcheck, those guys do PWM flickering mesurements using *something* (I don't know what particular device). I mean stuff like this:

http://www.notebookcheck.net/fileadmin/ ... wFile9.jpg

So it would be instructive to get any kind of such measurements in your case. And another stupid question: since you went as far as to change laptop's display, have you ever had a chance to do a 'test' on an entirely different T430? (Some other machine of the same type)?