Your problem seems due to VESA problems.
Maybe Linux initialises VESA (with the Framebuffer console for example)
or has VESA workarounds that NetBSD doesn't use? My guess
(a long shot, though) is it has something to do with initialisation.

It could be an idea to compare the dmesgs of both systems, if you still have
access to this Linux computer or partition.

Peter
-- 
http://www.student.kun.nl/peter.bex
--
"The process of preparing programs for a digital computer
 is especially attractive, not only because it can be economically
 and scientifically rewarding, but also because it can be an aesthetic
 experience much like composing poetry or music."
							-- Donald Knuth