Hi,

by default Ubuntu starts everything that is contained in a packages,
that could be auto-started, let alone that an Ubuntu desktop flavours
install tons of services you unlikely need at all.

Consider to install Ubuntu from e.g. the server image, after
unchecking all recommended packages. Then install just what you need
and after installing a package, disable all unwanted auto-start stuff,
or use a distro, e.g. Arch Linux, that follows another approach and
btw. provides rt patched kernels.

Regarding Intel I don't have experiences, but I often read that
hyperthreading seems to cause issues.

Regards,
Ralf