TL;DR Installed the Mar 8 lubuntu 15.04 daily build and sound doesn't work at all, but overall better than a stable release. What can I try?
I'm using the newly released Thinkpad X250 which has one of the 15 W Broadwell processors. I've read posts detailing the various steps involved in getting vanilla Ubuntu 14.04 and 14.10 working with the laptop so I decided to give the current state of 15.04, especially because I'm interested in getting the the newest stable graphic drivers for the graphics integrated into the processor.
I downloaded the Friday March 6 2015 lubuntu daily for the 15.04 (http://cdimage.ubuntu.com/lubuntu/daily-live/current/) 64 bit image and the installation went very well, except that full disk encryption with LUKS failed, citing some swap space that may allow for partial recovery of the encryption key. The freshly installed operating system worked great - the linux version of Team Fortress 2 ran at respectable frame rates at settings i found acceptable, the trackpad works well enough (no side scrolling), trackpoint works, wireless lan works like a dream, and brightness changing buttons work as expected.
The main problems are that the trackpad buttons are mapped to different (and useless) keypresses and that the sound doesn't work at all. Is there anything I can try to enable sound on the machine other than hoping for a fix via sudo apt-get update; sudo apt-get upgrade
?