I installed ubuntu server 11.10 on my macbook 1,1.

In order to reboot after power failure I have to set a specific "AFTERG3" bit using setpci.

The solution for a macMini can be found here:


Does anybody have an idea how to find out the corresponding command for my hardware?



I finally found the solution:

setpci -s 00:1f.0 0xa4.b=0

The poster in my linked question just forgot one 0.

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    Great work on figuring this out yourself. You should accept your own answer here (by clicking the tick on the left) so people in the future will know to read this one. – user2405 Nov 12 '12 at 8:27

The technical reason for using the setpci -s 0:1f.0 0xa4.b=0 magic is described here:


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Just a minor correction: After checking the setpci command, it would be more appropriate to use

setpci -s 0:1f.0 0xa4.b=0:1

as this will only set bit zero to zero (0 = value : 1 = masq ).

It does not matter in this case since all the other 7 bits of pci 0:1f.0 address 0xa4 are already zero, but that might not be the case for other hardware.

Use the sudo lspci -vvvxxx command to see what your 0:1f.0 pci device initial configuration is before making any mods.

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