This is the problem. Your CPU doesn't support an instruction that Armory is frequently compiled for. Please try the latest noasm build: https://github.com/goatpig/BitcoinArmory/releases/download/v0.96.5/armory_0.96.5_amd64_gcc4.9_noasm.deb

Note that a lot of Armory is Python rather than C/C++, but if using gcc4.9 does not work properly you can try a 0.96.4 noasm build or you are going to need to compile your own version.

Unfortunately that is the old Armory website (https://btcarmory.com/ is the maintained site). The current Linux build notes will work a lot better.