Hi,
Onto what part does it flicker or shutdown? Here are some troubleshooting steps that may help.
- Do a hard reboot first, remove the battery and unplug the AC adapter then press and hold the power button for 20 seconds then try booting it up again.
If this will not work, do test the AC adapter if it's working properly. Remove the battery and power the laptop with just the AC adapter connected and see if it will boot up or not. do also try a different AC adapter that has the same voltage and see if it will work or not.
- Proceed with reseating the RAM's if trying a different AC adapter will not work, remove them all for couple of seconds then put them back in making sure everything is seated properly.
- If it will still shutdown by itself, and if you have a extra HDD do try it and install Windows then see if the same problem will persist or not.
- If all these will not work, I would suggest contacting ACER if the laptop is still under the factory warranty.