Last year I purchased a Lenovo P620 with Ubuntu for use as my primary machine, and I’ve been pretty happy with it so far. It comes with a rear audio card, as one might expect, but also a separate, front audio card, that handles the headphone jack but also, curiously, contains a lo-fi speaker. My guess is that, as a workstation, having lo-fi onboard audio was good enough for most intended use-cases.