From: andreas@knobel.knirsch.de (Andreas Klemm) Subject: Re: help with system to run unix Date: Mon, 30 Aug 1993 12:49:45 GMT
Hello !
I have some *remarks*
concerning local bus video cards
in conjunction with
bus mastering scsi controllers like the aha1542x.
I have a 80486/33 EISA board with a normal local bus slot - no vesa
local bus - and a ET4000-16 based local bus video card.
X11 performance is _very_ bad when having disk i/o (nn, relaynews).
drew@juliet.cs.colorado.edu (Drew Eckhardt) writes:
>In article <25opra$ohe@news.ysu.edu> ag173@yfn.ysu.edu (Jay Hauben) writes:
>>She has been quoted a price for a system at the upper limit of
>>what she can afford. The system consists of the following
>>components. Does anyone see in this system anything that would
>>prevent her needs from being met? Might any of the components be
>>too weak for what she wants to do? The forms of UNIX she might
>>have available are Minix (which appears not to have uucp)
>>and off the net Linux. She has a 2400 baud modem now and hopes to upgrade
>>it and maybe buy a CD-ROM player and controller some time in the
>>future when she is in a position to afford them.
>>
>>The system she has the quote for consists of:
>> 5) 4 MB RAM expandable to 64 MB. (Should she insist on SIMM
>> chips?)
>Every modern system uses some form of SIMMs, 9 or 36 bits wide.
BTW: Look for good 70ns 4 Mbit SIMM banks.
>If she wants to run X, 8M is recommended, if she turns off all the
>drivers she isn't using to reduce kernel bloat and doesn't run X,
>4M will be useable.
>>11a) Trident 1 MB SVGA video card with a DC 009 IDE controller
>> card
>Trident boards are dog slow. A cheap alternative (I've seen new for
>for $60) would be a TSENG et4000 based board.
Ok, perhaps better using some of the S3 Chip based Vga boards as the
Orchid Fahrenheit 1280 ?! It certainly improves X11 performance a lot.
>>11b) Genoa IMD VESA local bus graphics card with a VLB IDE
>> controller card (for about $150 more). (Is there a significant
>> advantage gained for the extra money even though she doesn't
>> anticipate doing much graphics?)
I wouldn't suggest using a local bus card in connection with
an Adaptec SCSI controller which does DMA busmastering.
I have here a ET4000 local bus card for testing. The cpu has
to wait, if the SCSI controller does heavy disk/DMA activity,
therefore X11 graphic output has to wait, too.
Then when you have lot's of X11 window/scroll activity, the
cpu does exclusively access to DRAM.
I have the certain feeling, that local bus video cards and
a scsi controller acting as bus master handicap each other !!!!!
>If she wants to run X, I'd suggest going with 8M of memory, trading
>the 486DX-33 for something slower like a FPU less Cyrix 486DLC or even
>a 40Mhz AMD 386 as price concerns dictate. The overall performance
>will be better when things run in real memory, not swap.
8 Mb is the absolute minimum ! better 12 or 16 MB !!! Really.
-- /-\ Andreas Klemm <andreas@knobel.knirsch.de> +-----------------+ |@|########################################################-@ "pay for it !" | \-/ 41469 Neuss Germany phone +49/ 2137 12609 +-----------------+