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- Xref: sparky comp.unix.pc-clone.32bit:1335 biz.sco.general:5579 comp.unix.sys5.r3:414 comp.unix.sysv386:17909
- Path: sparky!uunet!math.fu-berlin.de!news.th-darmstadt.de!adams
- From: adams@pdv2.fmr.maschinenbau.th-darmstadt.de (Adams)
- Newsgroups: comp.unix.pc-clone.32bit,biz.sco.general,comp.unix.sys5.r3,comp.unix.sysv386
- Subject: Re: PC Unix/Xenix vendors
- Date: 25 Jan 93 23:05:27
- Organization: TH-Darmstadt
- Lines: 56
- Message-ID: <ADAMS.93Jan25230527@PDV2.pdv2.fmr.maschinenbau.th-darmstadt.de>
- References: <C188DI.EHE@ddsw1.mcs.com> <2B6010B6.14DF3@tct.com>
- <ADAMS.93Jan23013219@PDV2.pdv2.fmr.maschinenbau.th-darmstadt.de>
- <C1DCED.D19@ddsw1.mcs.com> <2B640EE0.675B@tct.com>
- NNTP-Posting-Host: pdv2.fmr.maschinenbau.th-darmstadt.de
- In-reply-to: chip@tct.com's message of Mon, 25 Jan 1993 16:01:36 GMT
-
- To:
- In article <2B640EE0.675B@tct.com> chip@tct.com (Chip Salzenberg) writes:
-
- > According to karl@ddsw1.mcs.com (Karl Denninger):
- > >Certainly, [PC clones] have the installed base now. But these
- > >"installed" systems do not play well together, they're unstable (ask
- > >any DOS user) and to get away from that is just too damn expensive.
-
- As DEC was able to build a binary compiler VAX executables to alpha,
- same should be possible for a less complex architecture like 386.
- How about jsut to compile your 386-Windows-3.1 excutables into
- R4000-IRIX-X-executables? Impossible? ...would not bet !
-
- > It's DOS and Windows that are unstable, not the hardware architecture.
- > Contrast UNIX on a PC clone: it keeps going, and going, and going...
-
- NO!
- Besides the problems with Intel CPUs, just remembering the
- problems aorund B5/B6 and C0/C1 stepping of 80386,
- DMA/Floating Point Exception/Cache_miss_fill of 80486,
- beside the problems given by current glue chip sets, you should remember:
-
- The AT bus was NEVER designed for HIGH PERFORMANCE system, but
- cheap. It lacks a well thought timing [ yes, please refer to the
- standard, some address lines are to be latches/decoded, before they
- are even generated].
-
- The bus lacks well defined specifications of electrical impedance, no
- adequate [ at actual impedance, guessing around 130 Ohm] termination
- is even suggested. This would have required more powerful drivers on
- both the add on cards and mother board.
-
- This makes the implementation of the ISA bus sensitive against small
- shifts in timing and phase (dispersion[correct t.t ??) of signals.
- (Sure, you did never see a PC going south, just by adding one card
- more, did you? IRQ-, DMA- and address conflicts excluded prior.)
-
- Here around are two similiar equipped 386-PCs with ISA bus,
- one 386-25sx, the other a 386-33dx. The DX does not even like
- to boot the Linux-0.99-p4 kernel, the SX is running since
- appearance. So much about comatibility....
-
- > "Goes away from DOS" ... to systems that support DOS applications,
- > like OS/2 and Windows and modern UNIX VP/ix or DOS Merge or SoftPC.
- > Those real people-use-'em DOS apps won't disappear for a decade or so.
-
- Why? They are now substituted with programs having similiar user interface
- (lock and feel), will be able to handle the old data, but
- nothing more.
-
- Why should any system addministrator like the hassle with
- extended and expanded (or was it just expected) memory,
- lack of user and process isolation(viri ...). Tell me why?
-
-
- best, adams
-