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- Path: sparky!uunet!zaphod.mps.ohio-state.edu!sdd.hp.com!hpscit.sc.hp.com!matthias
- From: matthias@nsr.hp.com (Matthias Kamm)
- Newsgroups: comp.sys.ibm.pc.hardware
- Subject: Re: Bunch of PC questions?
- Date: 29 Dec 1992 01:16:09 GMT
- Organization: Hewlett Packard Santa Clara Site
- Lines: 48
- Message-ID: <1ho8spINNfb7@hpscit.sc.hp.com>
- References: <1992Dec25.185547.11983@mnemosyne.cs.du.edu>
- NNTP-Posting-Host: hpmvd069.nsr.hp.com
- X-Newsreader: TIN [version 1.1.2 PL7]
-
- Neal Wickham (nwickham@nyx.cs.du.edu) wrote:
- :
- : Is the EISA bus and Microchannel the same thing? They are both 32-bit
- : If not the same, which is better?
-
- Microchannel is IBM proprietary, while EISA (Enhanced ISA) is an industry
- standard. I believe there isn't much performance difference. Both are much
- better than the old ISA (Industry Standard Architecture).
- I was a little shocked at the time of the microchannel introduction. IBM
- had originally released such an OPEN machine in the original IBM-PC, and
- here they are trying to bring everything in house again. It just isn't
- popular, and you now see IBM re-releasing ISA boxes due to market pressure.
-
- :
- : ISA is just the old AT 16-bit bus, right?
- :
- yup.
-
- : Why is that? What does the EISA bus have a big effect on? I thought
- : anything going down the EISA bus would go twice or more as fast?
- :
- I think the problem is that software, and lots of hardware doesn't
- yet take advantage of the 32-bit bus. If you buy an EISA system,
- you're hedging for delayed obsolesence of your box.
-
- : Are 386 systems usually socketed for the math co-processor?
- Yes. You can buy an Intel, IIT, Cyrix, or other 387 to work with
- your Am386.
-
- : How do you rate video card speed. The resolution and # of colors is
- : simple enough but I understand that the gfx speed is very important to
- : overall performance? How do you tell fast cards from slow ones?
-
- The latest issue of BYTE contains a complete listing of benchmark
- performance ratings of new video cards (windows accelerators). Check
- it out before you buy.
- :
- : Oh... and here's the one that's been bugging me for a long time. I know
- : that the 386 is a 32-bit chip internally and externally and that the 386sx
- : is 32 internally and 16 externally, but if you stick them both on an ISA
- : 16-bit bus, why is the 386 so much faster than the 386sx?
-
- Almost all motherboards these days (even up to 3-4 years ago) used a 32-bit
- wide local bus which ran from the processor to the memory. That's why
- Compaq and others had special memory cards, or memory expansion boards.
-
- good shopping,
- Matthias
-