GIMP and Abiword are definitely available for BSD, both are open source and use the GTK+ toolkit on X11.
- ATI/AMD is good in the open source community, they contribute GPU documentation and paid developers to work on a open source driver for Xorg, which works on BSD and Linux.
- ATI/AMD releases a proprietary driver (..catalyst/fglrx) for Windows and Linux, but not for BSD.
- nVidia has a proprietary driver for Windows, Linux, and FreeBSD (..which obviously includes PC-BSD, which is a distribution).
- nVidia has no open source inclinations, they release no documentation, and recommend their proprietary driver or the unaccelerated VESA on non-supported OS's.
Those of us using OpenBSD/NetBSD have no proprietary graphics drivers, and speaking for myself I wouldn't use them if they existed.. proprietary code in kernel space is a recipe for disaster.
Insulting people because you're unable to do your own research won't get you anywhere.. asking for a list of compatible hardware is flawed, a computer is made up of a lot of different components.. it is up to you to find a system with those components, people can only give you their preferences.