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I installed Ubuntu (12.04) on my Acer Aspire 5734z and the back light stopped working. I have tried the fix by editing the grub file posted on here a couple of days ago but that hasn't fixed it. I have also looked for hardware drivers but that didn't get me anywhere. When I hook up an external monitor it works fine but I have been unsuccessful getting the laptop display to light up.


edit removed link

I found a fix here " " if anyone has a better fix than the one in that post, let me know.

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try executing sudo setpci -s 00:02.0 F4.B=00. Let us know if it works. – Web-E May 11 '12 at 6:11

Nope didn't work, once you reboot, it's back to step one. I spent almost 2 hours looking for a damn solution and thank the lord almighty I found it! :D I also have an acer aspire 5734z.

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Welcome to Ask Ubuntu! Whilst this may theoretically answer the question, it would be preferable to include the essential parts of the answer here, and provide the link for reference. – Peachy Sep 27 '12 at 0:57

web-e's setpci command (from the comment) helps me:

setpci -s 00:02.0 F4.B=00

Now the backlight changes.

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