Eu segui este responda e instale a versão de 64 bits do kernel.
uname -m print x86_64 , então está funcionando.
Quando tentou instalar o Chrome de 64 bits, o Centro de Software reclamou de libcups:amd64 . Tentei instalá-lo manuelly, mas eu tenho
sudo apt-get install libcups2:amd64
.....
.....
The following packages have unmet dependencies:
kde-runtime : Depends: libsmbclient (>= 2:4.0.3+dfsg1) but it is not going to be installed
Recommends: kubuntu-debug-installer but it is not going to be installed
libcups2:amd64 : Depends: libgssapi-krb5-2:amd64 (>= 1.10+dfsg~) but it is not going to be installed
E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.
Isso não deveria funcionar apenas com multiarch? Se não, como instalar pacotes de 64 bits?