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- Path: sparky!uunet!ogicse!uwm.edu!ux1.cso.uiuc.edu!news.cso.uiuc.edu!uxa.cso.uiuc.edu!nap42487
- From: nap42487@uxa.cso.uiuc.edu (Nishith A. Patel)
- Newsgroups: comp.os.os2.misc
- Subject: Re: Does VESA Local Bus put a huge strain on a CPU?
- Message-ID: <BxBvCA.DHv@news.cso.uiuc.edu>
- Date: 7 Nov 92 04:04:56 GMT
- Article-I.D.: news.BxBvCA.DHv
- References: <82994@ut-emx.uucp> <23700@galaxy.ucr.edu>
- Sender: usenet@news.cso.uiuc.edu (Net Noise owner)
- Organization: University of Illinois at Urbana
- Lines: 30
-
- insom@watnxt06.ucr.edu (Chris Ulrich) writes:
-
-
- > Local bus is useful for only dumb frame buffers. Frame buffers
- >such as SVGA cards require all the bandwidth they can get, and
- >also require the CPU to do anything. I suppose this would also
- >hold true for sound cards and digitized sound.
-
- >not CPU cycles, because they would be conducting the transfer
- >themselves. The CPU in EISA systems is still able to function
- >out of its cache or access non locked memory (memory not accessed
- >by the busmaster).
- > Local Bus is not even a decent solution to video. A real video
- >standard would have the video memory located at the top of the
- >memory map (all of it, not in 64k chunks), a smart coprocessor,
- >and DMA.
-
- A Local Bus card can be coprocessed. Just do that.
-
- > Unless Local Bus standardizes interrupt sharing and multiple
- >busmasters, it is not an acceptable replacement for EISA.
- > Of course, that doesnt mean you shouldnt have both...
-
- Well, all I care about is fast video. getting a ISA+Local Bus is good enough
- fr video, because going to EISA+Local Bus won't help you any. So I am basically
- just forgetting about EISA here, not worrying about whether it is a better
- bus for all-around performance or something. What I am still trying to figure
- out is whaT local bus implementations are the best, because all of them are
- definitely not created equal. Some are implemented poorly. I am trying to
- figure out which ones are implemented well, giving the best performance.
-