Thinkpads Forum

Does anyone here has the same issue as mine, i.e. I cannot control the brightness of the screen (nothing happen when I pressed Fn-Home or Fn-End) when my X200 and X201 returning from sleep mode?

I have that same problem on my T400.

Haven't found a solution but noticed it does that on AC only and not DC. I think it may be some kind of Power Management bug. I'm running XP Pro SP3.

Good to hear that I am not the only one having this issue. I am running both Vista and Windows 7 on each of the machine and they have the same problem. Hope someone can advice us what is the issue.

Just tried a little experiment as I am using my Ubuntu boot.

There is no annoying brightness glitch in Ubuntu 9.10 upon awakening from sleep. It seems to be a MS thing. I did not know that it happened in W7 also. Thanks for posting that information.

Happens to my X301 with W7 also. Sometimes closing and opening the screen restores functionality.
Also, it will hang when I try to shut it down after it does that. I think it is a problem with the power manager and windows 7.
System update just updated the power manager (changed the way the on screen brightness/volume shows up) so ill report back with how its working.

It can't be a windows bug, it is a bug in the embedded controller firmware, since you don't need windows or any OS to control brightness. Sometimes it stops reacting to the brightness key combinations. The fact that it does so when using windows does not show that it is a windows bug. More like a firmware bug, it hangs when it sees some stuff written into some of it's registers that it doesn't "know" how to interpret or what to do about it. Lame bug, if they can't solve it, they should at least make it ignore that written stuff :/

yozas wrote:It can't be a windows bug, it is a bug in the embedded controller firmware, since you don't need windows or any OS to control brightness. Sometimes it stops reacting to the brightness key combinations. The fact that it does so when using windows does not show that it is a windows bug. More like a firmware bug, it hangs when it sees some stuff written into some of it's registers that it doesn't "know" how to interpret or what to do about it. Lame bug, if they can't solve it, they should at least make it ignore that written stuff :/

That's fine and dandy but can you explain why I don't have that problem on my Ubuntu boot?

I'm just wonderin.'

Most probably because it doesn't write anything (communicate with it, etc) to that place like windows does? But in long perspective that doesn't really mean it's better solution, some potential functions are probably being counted out, and when the time comes to use them, then exactly the same problems might show up. This is a good example of a case when an OS that doesn't support something can be a good thing, a way of avoiding provoking a bug in an embedded controller.

The most recent Power Manager update has fixed this issue for me

That's very possible, though I don't see any new version of it available. I'm using latest myself, and this problem still comes up sometimes.

Its saying it is v. 3.12
I usually run system update and windows update every week/every other week so I feel like I would have seen the update, and run it.

Anyway, it completely fixed my standby/hanging issues ive been having.

I was having this problem on my X61 in Win7. In my case, I found that never setting the brightness to 0 avoids the bug.

It seemed to be random as to whether it would 'stick' or not, so I never found out if it was related to being on AC, DC or just sleeping with it at level 0.

Well.

I found out the other day in class that the bug has struck my T400 again. I had put it sleep and when I awakened it the brightness was at max again. Hotkey for brightness did not work and I'm somewhat disappointed in Lenovo. I hope this gets fixed soon!

I'm also very angry at Intel, because the wifi card that the x301 has gives a lot of problems, or it did for a year or so at least, with 64bit windows. Bluescreen crashes when wifi activity is high and sometimes random crashes. I can't believe those lazies couldn't fix their product drivers or firmware for a year or more! This seriously ruined the reputation of X301 and other notebooks that got the "luck" of having Intel 5100/5300 wifi card inside. Now they've released a driver that alleviated the problem somewhat, but it still exists.

Intel sleeping over the past prizes?

Anyway, I am not getting the expected stability, etc. out of my X301 (and I do have in depth experience with notebooks), that I had with X41, T43 and I just can't believe it.

This happens on the X200T, but using the tablet screen options button, third towards the right from the power button, brings up the Tablet Options menu window, and the screen brightness can be controlled from there.

Happens here too. I use Win+X (Mobility Center) to change the brightness then.

Investinwaffles wrote:Happens to my X301 with W7 also. Sometimes closing and opening the screen restores functionality.
Also, it will hang when I try to shut it down after it does that. I think it is a problem with the power manager and windows 7.
System update just updated the power manager (changed the way the on screen brightness/volume shows up) so ill report back with how its working.

February 2011 and this issue is still happening (in my case, when restoring from hibernation) - X201, Win7 32bits, fully updated as of today, including this month's BIOS update and last month's graphics driver.

The trick of closing the lid and opening up again worked. I noticed that when the hotkeys stop responding, also the WinKey+X menu (Windows mobility center) stops showing "Display Brighness" as an entry.

Started noticing the problem today. Noticed a bunch of Win7 updates last week.

I am a bit tired of lenovo/microsoft's crappy software ruining what otherwise would be nice user experience, in remarkable hardware.

Wondering if anybody knows the root cause of the problem.