Irritating screen flicker Intel GMA4500 with X-ORG 7.6

[vistapete]

Hi all.

I am running a USB install of TC with X-ORG 7.6 - which sets the screen res/depth nicely but on my aspire 5738z which has intel GMA4500 the screen flickers.

According to the display manager the res and refresh are as expected - 1366x768 @60Hz

To my mind it looks like the backlighting that's the problem (LED) - the appearance is almost like that of a faulty discharge lamp flicker except it never goes off just flickering like it's hunting between two close brightness levels in a random fashion at very annoying frequency - guessing around 40Hz or somesuch.

I haven't noticed this  when I boot my eeepc which is also LED backlit but employs the GMA950 - to be fair it's a much smaller screen too, but I think the flicker would still be very noticeable.

I don't recall being bothered by flicker before installing X-ORG but that was a much lower resolution if that makes any difference.

It's bad enough to be unuseable on the Aspire. Any ideas? Thanks.

[Rich]

Hi vistapete
If you have any fluorescent lights in the area, turn them off. If the flickering stops, maybe consider
a desk lamp with an incandescent bulb.

[vistapete]

As per the OP it's definitley the screen (does it in the dark too!).

As it happens I did some research which pointed me to a partial fix - the screen on the Aspire is VERY bright so I usually operate it wound down to almost min brightness.

I now know that the screen brightness is set at whatever I had it on last in Windows. In Windows no flicker is visible irrespective of the brightness, but I read that some LED panels modulate the frequency of the backlight to achieve dimming which can lead to flicker.

I turned the brightness up a few notches in Windows and rebooted to TC and the flicker is now almost absent - certainly I can use it without discomfort.

I assume the dimming method is controled by the driver which for the TC instal introduces the flicker at low brightness levels (?)

Now if only I can control the brightness in TC .... and find where my Thunderbird installation has dissapeared to  I'd be sorted.

[Rich]

Hi dvistapete
It's possible the lack of flickering under Windows is due to a different resolution and/or refresh rate.

[DustinElliott]

Hi all.

I am running a USB install of TC with X-ORG 7.6 - which sets the screen res/depth nicely but on my aspire 5738z which has intel GMA4500 the screen flickers.

According to the display manager the res and refresh are as expected - 1366x768 @60Hz

To my mind it looks like the backlighting that's the problem (LED) - the appearance is almost like that of a faulty discharge lamp flicker except it never goes off just flickering like it's hunting between two close brightness levels in a random fashion at very annoying frequency - guessing around 40Hz or somesuch.

I haven't noticed this  when I boot my eeepc which is also LED backlit but employs the GMA950 - to be fair it's a much smaller screen too, but I think the flicker would still be very noticeable.

I don't recall being bothered by flicker before installing X-ORG but that was a much lower resolution if that makes any difference.

It's bad enough to be unuseable on the Aspire. Any ideas? Thanks.

hello were you able to sort out the problem? I am facing similar issue with screen..it flickers a lot.. Can you tell how to solve it?Waiting for reply thanks in advance:)

[coreplayer2]

I have the opposite issue with one monitor,  example it flickers a little but only when connected to an Mac + OSX,  when connected to the same Mac + tc + Xorg there is no flicker at all..

I think I'll take Rich's hint and try adjusting the resolution and refresh rates