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- Path: sparky!uunet!olivea!hal.com!decwrl!mips!darwin.sura.net!Sirius.dfn.de!math.fu-berlin.de!news.th-darmstadt.de!adams
- From: adams@pdv2.fmr.maschinenbau.th-darmstadt.de (Adams)
- Newsgroups: comp.sys.ibm.pc.hardware,comp.sys.intel,comp.sys.ibm.pc.misc
- Subject: Re: More on Local Bus - What about Unix?? S3 vs.
- Message-ID: <ADAMS.92Aug13004812@PDV2.pdv2.fmr.maschinenbau.th-darmstadt.de>
- Date: 13 Aug 92 00:48:12 GMT
- References: <0105010F.ac48r9@mprnews.mpr.com>
- <1992Aug10.092255.118@vulcan.resmel.bhp.com.au>
- <Bss82v.LJM@usenet.ucs.indiana.edu>
- Sender: news@news.th-darmstadt.de (The Usenet-News System)
- Organization: TH-Darmstadt
- Lines: 32
- In-Reply-To: ntaib@silver.ucs.indiana.edu's message of Mon, 10 Aug 1992 19: 13:43 GMT
- Nntp-Posting-Host: pdv2.fmr.maschinenbau.th-darmstadt.de
-
- In article <Bss82v.LJM@usenet.ucs.indiana.edu> ntaib@silver.ucs.indiana.edu (Iskandar Taib) writes:
- >
- > A penalty compared to what? No video?
- >
- > What you imply here is that the PC doesn't communicate with its
- > video subsystem if it doesn't have a coprocessor. As a matter of
- > fact it does. It takes up so much bandwidth that it limits video
- > speed. A coprocessor reduces the amount of stuff that has to be
- > sent via the bus and that is why we see huge speedups when using
- > coprocessed video cards.
- >
-
- You are right !!!
-
- 1) Without a coprocessor, graphic in a PC means bit manipulation by CPU.
- This may eat up most of the available bandwidth.
-
- 2) As a coprocessor allows to use protocols at a much higher level,
- like X or Phigs, communication overhead _shrinks_ tremendously.
- This has been proven with PC-graphic adapters running Xserver themselves,
- no CPU had to write to video memory anymore.
-
- best, adams
-
-
-
-
- --
- -------------------------------------------------------------------------------
- Iskandar Taib | The only thing worse than Peach ala
- Internet: NTAIB@SILVER.UCS.INDIANA.EDU | Frog is Frog ala Peach
- Bitnet: NTAIB@IUBACS !
-