From: copes@cs.curtin.edu.au (Simon Cope)
Subject: Stuff
Organization: Curtin University of Technology
Date: Wed, 9 Sep 1992 05:43:09 GMT


>>|  >BTW, last week I read a comparison test between 14 486/50's.  They all ran 
>>|  >around 400-500k sec on the Hdisk tests
>>|  
>>|  What a crock of shit, my 386/33 with IDE pulls around 850k/s.
>>
>>What a pathetic piece of shit (the 386/33); my 68020/20 with SCSI "pulls"
>>1.5Mbytes/Second tested on 50MB and 100MB files.

Too True.

>Be fair now.... who built the mechanisms?  What types of drives are we 
>talking about here?  In general, on equivalently fast mechanicals, SCSI
>seems to be faster on long file reads than IDE...  IDE sometimes wins out
>on smaller files though.

Also True.  With small files, a SCSI system will spend more time setting up
the dma controller than actually transferring the files.  Thats why ide can
be faster on directory listings and small file access.  It is also why a SCSI
system can run faster with one drive if you turn off reselection, as normally
once a seek is set up, the controller will clear the dma channel for the next
op, so you can have one drive seeking while another is doing a transfer.  All
very good for multi drives, but with only one drive, it has to reload all the 
registers again.  I gained 100K sec by doing this.

>But.... in the final analysis... you're right.  850kB/sec is okay, but it's
>hardly anything to get really hot and bothered about.

Which is the point I was trying to make, but things get clouded by friday arvo.
What I meant was that C= would be silly to go for a drive that is only half
the speed, just to save 10 bucks.  They might do it on the lower machines, 
however, such as the rumoured A2400, but a high end machine will be bought by 
people obsessed with speed.  Fast ZorroIII scsi-II controllers might become
a big seller for the lower range machines, when someone gets around to making 
one.  The low end machines such as the A600 and A2400~ will be aimed at mass
sales, while the high end ones will be aimed at max profit.  Rumour has it 
that the A600 retail price is projected at $300 once they cover their design
costs.  The next machine up the range is aimed at around $1000, while the top
end machines will be pretty expensive, but worth it. 

I will also concede that drive speed depends a lot on the particular mechanism
used.  The 486's had drives around the 200M mark in them, but I don't know
what make they were.  Probably the cheapest, to cut the cost down.  What size
is the drive in that 386?  A 240M Quantum is 2x the speed of a 120M, because
of the higher bit density.  On the same front, I read a review of the GVP HC/8
card in an A2000.  With a 240M Quantum, they claimed it was 30% faster across
the board than an A3000 with a 220M Fujitsu drive, which means the A3000 was
only running around 550Kb/sec.  My own A3000 with 52M Quantum runs around 930K
sec, which means that either the Fujistu is installed wrong or its a heap of 
bog.  Most cheap PC clones will be installed with cheap drives, and you only
get what you pay for.  An EISA SCSI card would bump up the price of a PC a bit.

Down here, an A3000 25/50 minus monitor is A$2650, $700 cheaper than when I 
bought mine just before easter.  Pick one up for $3000 with monitor, and its
competing comfortably with a decent clone.  Except in Software.  But then, who
needs 50 different word processors.  I mean, you can only run 1 at a time on a
PC, unless you go put and buy a decent OS for it.

The A600 may be more expandable than C= is letting on at present.  Apparently
there is a bunch of unused circuitry on the board.  Golem of germany have
announced an 030 accelerator for it which DOESN'T require the 68000 to be
chissled off the board.  Figure that one out.            

BTW: The whole discussion on OS's is pretty irrelevant.  DOS was the OS of the 
80's, Unix will be the OS of the 90's.  The only thing holding it back right 
now is recession.  I haven't met anyone here at cs or over in engineering who
doesn't like Unix.  Everyone likes it, over anything else they use.  Including
MSDOS, OS/2, AmigaDOS, VMS etc.  Everyone tries to do their projects on a Unix`
box (we've got sun, sgi, dec (maspar), HP) and everyone want's a job in Unix.
AT&T's strategy of giving big discounts to unis for unix has worked, because  
now they've picked up a lot of devotees.  When C= ship Amix 2.1 here I'm going
to buy it.

 
>-- 
>Jerry Kuch (t-gerldk@microsoft.com) | "Sic Gorgianus Allos Subjectatus Nunc."
>  "I was wrong to play God.  Life is precious, not a thing to be toyed with.
>   Now take out that brain and flush it down the toilet." - Montgomery Burns

--
copes@cs.curtin.edu.au