Comment 2 for bug 1647184

After struggling this for the better part of a week, the best solution I have found is to abandon the Ubuntu 16.10 installers entirely and use debian-8.6.0-amd64-i386-netinst.iso which works perfectly on a MacBook Pro 3,1. A workable approach I believe is to do as bare-bones an installation as possible in Debian Jessie followed by swapping out the /etc/apt directory for one from Yakkety and then doing an 'apt-get update' and 'apt-get dist-upgrade'. The last step is to manually search for all of the packages installed that not part of the Ubuntu repo and deinstalling them.

For the next release, you seriously need to consider rolling an equivalent installer ISO as the Debian amd64-i386-netinst.iso. In fact, it is only

$ ls -l debian-8.6.0-amd64-i386-netinst.iso
-rw-r--r-- 1 howarth howarth 584056832 Dec 7 18:08 debian-8.6.0-amd64-i386-netinst.iso

so you might consider swapping out the existing Yakkety net installer with a similar multi-arch copy.