Macbook Pro 17" mid 2010 can't install Ubuntu 10.10
I have a Macbook Pro 17" mid 2010 and I'm trying to install Ubuntu 10.10 on it.
The thing is that I bough myself a datadoubler from macsales.com so I could replace the CDROM with an harddrive instead.
Now I want to install Ubuntu on this disk but I can't seem to boot up properly into Ubuntu.
I have tried making a USB-stick with Ubuntu 10.10 on it but it doesn't get recognized neither in rEFIt or if I hold down the option-key during boot, it get recognized fine in OS X though.
I then tried hooking up a external CDROM and now I can see the CDROM choice and boot from the CD. BUT, I don't get the graphical interface that I get on my PC, I only get a Grub menu with the same choices that I get from the graphical, "Try Ubuntu" and "Install Ubuntu" but it doesn't matter which one I choose because I only get a black screen and eventually the CDROM spins down to a complete halt and nothing happens. I had it like that for about 30min just to be sure but nothing happened.
Is it only possible to install other operating systems using the internal CDROM?
And if so, how can I get a Linux installation on my second drive that I have instead of my CDROM.
I can, if necessary, switch back so I have the CDROM in but then I would have to switch the harddrives as well if I want it installed on my sencond drive and Then I would probably have to install OS X on it too and remove it later!?
What's wrong here and how can I fix this the best way?