lol, I've read your message and it looks... weird
anyway you've allready got an answer:
https://marc.info/?l=openbsd-misc&m=150615418409402&w=2
So it looks like your graphics card is supported by kernel, just wait when the bug will be fixed in Xenocara. You may try snapshot (maybe they've allready fixed that bug):
https://ftp.openbsd.org/pub/OpenBSD/snapshots/