I have 2 servers, HP Proliant ML110 G6 quad core xeon, which I keep in sync, the only difference is the backup server has no A400E card in. Both servers run Ubuntu 12.04 with the 3.2.0 kernel. 3.2.0-43 works on both but any later kernels only work on server without the A400E in. More info on
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1202405.