This short walkthrough describes how to install the Ubuntu Linux Kernel 4.0 (server and desktop/client) without compiling.

This guide should work with the latest version of Ubuntu Linux and most Ubuntu-based distributions including Mint. The included kernel files have been compiled using the generic Ubuntu configuration. The general packages are available for 32 bits systems (I386+) and 64 bits (AMD64) and ARMHF. I will not provide low latency versions.

Installation Guide (GUI)

1. Download the kernel headers package:
   
   http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.0-vivid/linux-headers-4.0.0-040000_4.0.0-040000.201504121935_all.deb
2. And the appropriate package for your system
   • AMD64:
     
     http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.0-vivid/linux-headers-4.0.0-040000-generic_4.0.0-040000.201504121935_amd64.deb
   • I386:
     
     http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.0-vivid/linux-headers-4.0.0-040000-generic_4.0.0-040000.201504121935_i386.deb
   • ARMHF:
     
     http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.0-vivid/linux-headers-4.0.0-040000-generic_4.0.0-040000.201504121935_armhf.deb
3. And the accompanying compiled kernel image
   • AMD64:
     
     http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.0-vivid/linux-image-4.0.0-040000-generic_4.0.0-040000.201504121935_amd64.deb
   • I386:
     
     http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.0-vivid/linux-image-4.0.0-040000-generic_4.0.0-040000.201504121935_i386.deb
   • ARMHF:
     
     http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.0-vivid/linux-image-4.0.0-040000-generic_4.0.0-040000.201504121935_armhf.deb
4. Install the files in the same order as downloaded above. So first install the headers (2 files) and finally the image (1 file).
5. In the terminal run:
   
   sudo update-grub
6. Reboot and select the kernel from the bootloader menu

I will post the latest version of the 4.0 branch and 4.1 release candidates in comments below.