There are a few features missing on T400S in Libreboot, which we have not yet merged in Libreboot.
https://lists.gnu.org/archive/html/libreboot-dev/2016-08/msg00027.htmlAre these patches present in your version of Libreboot for the T400S? They're not currently merged in Libreboot officially, so T400S won't work AFAIK unless you add them.
