Comment 135 for bug 546393

Im surprised to see MBP5.1 users having problems with booting into Ubuntu.
ive run ubuntu successfully for the last three releases when using the proprietary nvidia driver

What usually messed things up for me was what card was selected in OSX as the active card.
toggling this might be what gets you booted (my macbook has the 9600 and the 9400 nvidia card) into the installation.

Also , i run my macbook in efi mode nowdays, all works fine except that one needs to add a more up to date backlight module

adding this to grub console will disable your 9600 card before booting into your os and hence save battery.

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