[SOLVED] Doh! I forgot how to change screen resolution!

I have Ubuntu 13-10 running on my MacBook Pro retina 10,1.
It's running in EFI mode.
I've edited /etc/default/grub by adding the entry
i915.lvds_channel_mode=2 i915.modeset=0 i915.lvds_use_ssc=0
after "quiet splash". I *think* this turns off the Intel graphics chip.

I then installed nvidia-current (304.88, which is a bit old but nvm) and ran nvidia-xconfig. I then added the line
Option "UseDPLib" "off"
to the devices section of /etc/X11/xorg.conf

I rebooted and all is well :D Nvidia driver fires up and screen resolution is 2880 x 1800.
Things are very small :shock:

Therein lies the problem. Neither Nvidia's settings nor Ubuntu's normal screen resolution settings show any other available resolution than 2880 x 1800.
I went all through this about a year ago and I found a way to change screen resolution..................but now I can't remember what I did :(

Any suggestions please?
Thanks.