Re: 3.9 is (almost) here...
OK, so You want to use mainline kernel...
1. find kernel You want to use (go to http://kernel.ubuntu.com/~kernel-ppa/mainline/ and pick one, like with file on PC)
2. find 4 that are OK with Your architecture (3 for Your architecture and one with „all“ in its name)
3. DL them to Your machine
4.
Code:
sudo dpkg -i names_of_files.deb
Next time You reboot pick one that You've installed...
Ignota nulla curatio morbi.
Quod nocet saepe docet.