[comp.sys.mac.hardware] IIci internal video vs external video card?

gt4586c@prism.gatech.EDU (WILLETT,THOMAS CARTER) (11/16/90)

i know that using the internal video on my IIci slows down my CPU by some
30% or so when i use full 8 bit color.  if i bought a "normal" 8-bit video
card my cpu would be freed up to work faster.  however, what is the likely
effect on the speed of drawing to the screen?  will an external video card
draw faster or slower than the internal video?


-- 
thomas willett 
Georgia Institute of Technology, Atlanta  
gt4586c@prism.gatech.edu
"Violence is the last refuge of the incompetent." - Salvor Hardin (Foundation)

lemke@radius.com (Steve Lemke) (11/17/90)

gt4586c@prism.gatech.EDU (WILLETT,THOMAS CARTER) writes:

}i know that using the internal video on my IIci slows down my CPU by some
}30% or so when i use full 8 bit color.  if i bought a "normal" 8-bit video
}card my cpu would be freed up to work faster.  however, what is the likely
}effect on the speed of drawing to the screen?  will an external video card
}draw faster or slower than the internal video?

I don't have any benchmarks for you, but my own personal opinion is that it
wouldn't be worth it to buy just an 8-bit board.  Now, if you wanted to go to
24-bit (and maybe even accelerated) video, then it would be worth buying a
board.  But something tells me that one of the early IIci articles I read
indicated that even though in general built-in video is a burden to the CPU,
some things may even be a little faster since it doesn't have to use NuBus.
One thing to keep in mind is the fact that if you have different size SIMMs
in your IIci, put the bigger simms on the left.  An example is a 5mb IIci,
where the 1mb simms should be on the left, and the 256K simms on the right.
The built-in video will use the 256K simms and for the most part the Mac will
use the 1mb simms, and the overall effect will minimize performance degrada-
tion.

So, like I said, if you want 24-bit accelerated video, go for a board, but
otherwise, it's probably not worth the expense to just get an 8-bit.

These, of course, are my own opinions, and note that I have NOT recommended any
particular 24-bit board though I happen to work for a company that makes one...
-- 
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