First off, you should move to free software on the software side. Hardware is
a problematic part because there's no much alternatives here if you really
want 100% freedom. And ThinkPenguin doesn't sell such hardware, only the
company is commited to freedom. This means in practice that the seller (you
will meet him here under the nickname Chris) chooses regular HW components
that will work with a fully-free operating system, but anything beyond like
free BIOS is out of scope.
Coreboot is a software project that has the goal to replace the proprietary
(aka non-free) BIOS by mostly by reverse-engeneering, but now its backed by
AMD, and the main developers of the project is now funded by Google to work
on support of the Chromebook line of laptop computers. There are many
motherboards supported by this project, but even if you will choose to buy
one of them, you will still need to replace the BIOS, which is not something
anybody can nor will to do. Firstly because it's a complex procedure which
requires some knowledge, secondly because it may brick the hardware if not
handled carefully. I never done this before so I can't be for any help.
I think whether your HW is free software compatible or not, it's a good
starting point for elimination of the non-supported components, so that when
you change your operating system for a free software one, you will get such
features as 3D acceleration and working WiFi (the two most problematic, yet
easily solvable issues). Please, share with us the complete technical
description (i.e. list of components) of your current desktop so we will see
what can be improved.
