Travelmate P446-M screen blinks uncontrollably after sleep/suspend on Debian Bullseye

anti

I am running the latest Debian GNU/Linux stable on a Travelmate P446-M. Whenever the system sleeps or suspends (or even has the screen go black from lid close with power management settings set to avoid sleep, for obvious reasons) the screen comes back blinking/flashing between black and lock screen at about 1 second per full cycle between. I cannot type or click anything.

The only options to get the system usable again are Alt-Sys-Req-R-E-I-S-U-B or holding down the power key, but then...

the system turns on with a very faint lighting of the black screen but it hangs before even getting to the BIOS/boot, the Acer splash screen, or the grub loader. I must then power it down again. Eventually after doing this 15-25 times, it will boot past that point.

Another user documented this with a different Acer laptop and different Linux distro here and my symptoms are identical, though seemingly faster screen blinking.

Happy to try and find some logs if needed. Thanks in advance if anyone has any ideas.

[​//Edited the content to add model name]

Easwar

Hi @anti,

# Try to get the BIOS page.

1. Turn OFF the unit.

​2. Press and hold the F2 key and turn on the unit. 
3. You will be in setup utility page. 
4. Once you got the screen release the F2 key.
5. Tap on F9 key and hit enter key without changing the option.
6. Tap on F10 key and hit enter key without changing the option.
7. Your unit will restart by itself. 

Check this T/S and post the result. ​

anti

Hi,

Somehow missed your first reply, JackE.

(1) Yes, immediately after install. And happens every time I try to wake from suspend/sleep.

(2) Yes, installed alongside Windows, but the plan is to repartition the Windows drive and use it with linux if all converts smoothly.

Easwar: I will try to do so shortly and report back

JackE

>>>Somehow missed your first reply, JackE.>>>(1) Yes, immediately after install. And happens every time I try to wake from suspend/sleep.

(2) Yes, installed alongside Windows, but the plan is to repartition the Windows drive and use it with linux if all converts smoothly>>>

Did you uncheck Windows fast startup in Control Pane's power button app BEFORE you tried to install Bullseye? The reason is fast startup is akin to a warm boot with a low power drain to keep Windows boot remnants in RAM so they don't have to be re-loaded from disk. So it's really not a true clean full power off cold boot from which to boot the Linux installation stick.

Easwar

Hi @anti,

 Contact acer tech support,

https://www.acer.com/ac/en/US/content/service-contact​

OR book the unit for repair service,

https://customerselfcare.acer.com/CS2/#/

JackE

>>>Somehow missed your first reply, JackE.>>>(1) Yes, immediately after install. And happens every time I try to wake from suspend/sleep.

(2) Yes, installed alongside Windows, but the plan is to repartition the Windows drive and use it with linux if all converts smoothly>>>

Did you uncheck Windows fast startup in Control Pane's power button app BEFORE you tried to install Bullseye? The reason is fast startup is akin to a warm boot with a low power drain to keep Windows boot remnants in RAM so they don't have to be re-loaded from disk. So it's really not a true clean full power off cold boot from which to boot the Linux installation stick.