Comment 12 for bug 1245938

Hmm, that's strange that they don't boot. Can you also test the latest Trusty kernel from:
https://launchpad.net/ubuntu/+source/linux/3.11.0-12.19/+build/5088396

There are some hints on how to get further debug info from a boot failure at:

https://wiki.ubuntu.com/DebuggingKernelBoot

As mentioned on the wiki, it would be great if you can attach a log file which may have captured any messages you see. If you are unable to capture a log file, a digital photo will work just as well. As a last resort you can even copy messages down by hand.