The
radeon(4) man page lists ATI cards that are known to X. It is my understanding that basic 3d acceleration has been available via dri/drm capable ATI cards since openbsd 4.5 or so.
Edited to add:
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- The -current radeon(4) driver is xf86-video-ati 6.14.6. It's man page is the starting page of in the radeon(4) link in this posting.
- OpenBSD 5.2 will use 6.14.4 when it is released -- in a matter of days. It's man page is not yet available online (unless you want to browse the CVS repository for the applicable source).
- OpenBSD 5.1 uses the 6.14.3 driver, and its man page can be selected when browsing the online man page.