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Newsgroups: comp.unix.bsd.freebsd.misc Path: euryale.cc.adfa.oz.au!newshost.anu.edu.au!harbinger.cc.monash.edu.au!simtel!chi-news.cic.net!news.wctc.net!spcuna!ritz!ritz From: ritz@ritz.mordor.com (Chris Mauritz) Subject: Re: DNS, FTP & Mail - for ISP References: <44mmsd$1lda@news.gate.net> <44ro0o$r9l@tzlink.j51.com> <450eem$335@news.hal-pc.org> <450tf7$4n0@tzlink.j51.com> <454bpu$eev@uriah.heep.sax.de> <459tpi$g6v@tzlink.j51.com> <DG6nvu.7pE@ritz.mordor.com> <45cq5p$k16@tzlink.j51.com> Organization: Mordor International Date: Tue, 10 Oct 1995 05:58:49 GMT X-Newsreader: TIN [UNIX 1.3 950824BETA PL0] Message-ID: <DG7xy1.748@ritz.mordor.com> Lines: 54 Louis Epstein (lepslog@j51.com) wrote: : Chris Mauritz (ritz@ritz.mordor.com) wrote: : : Louis Epstein (lepslog@j51.com) wrote: : : : J Wunsch (j@uriah.heep.sax.de) wrote: : : : : Louis Epstein <lepslog@j51.com> wrote: : : : : >OK...where did you find a controller that handles a 9GB disk?The main ones : : : : >seem to stop at 8...which is why I ditched plans to use a 9 for news. : : : : : : : Why should a SCSI controller stop at 8 GB? : : : : : : : With 32-bit logical block numbers and the common value of 512 bytes : : : : per block, you can address : : : : : : : [arithmetic snipped] : : : : : : : 2048 gigabytes. : : : : : : Be that as it may,BusLogic and Adaptec are now making cards that can only : : : handle 8GB or smaller drives. : : : Um, both the Adaptec 2940 and the Buslogic 946C will handle 9gb drives. : : Just checked the web pages for both...the latter says 8 GB limit,the former : doesn't say a disk capacity limit,but they said it would take a firmware : upgrade when I called them(and I'm getting the 445 anyway). This is only applicable to DOS. You might be interested in what Paul Vixie has to say about building BSD/OS pc's. To wit: I'll start by recommending against VLB. VLB is the IBM PC of bus architectures. It has no parity on any signals, totally slipshod timing specifications, and no strong central authority telling hardware vendors what ``compliance'' means. Each VLB card is another ``load'' on the CPU/Memory bus. Since this bus was usually not designed to have more than three loads, you are at risk if you put more than one VLB card into your system. In fact if you put more than one VLB card into your system it will automatically slow the CPU/Memory bus down to make sure that each electron has a chance to visit all the voters. To combat this performance problem, motherboard designers have taken to putting a set of hardware buffers between the VLB and the CPU/Memory bus. The buffers present only one ``load'' to the CPU/Memory bus and therefore don't drag its impedence up and its speed down. But there are an awful lot of VLB cards out there that don't expect those buffers to be there -- and so when they arbitrate for bus ownership they can end up thinking they won at the same time some other bus member thinks that it won. Bad, rotten design. VLB is good enough for video since data errors won't be persistent. Using VLB for networking or storage is like wearing a ``kick me'' sign on your backside. Heh. Chris -- Christopher Mauritz | For info on internet access: ritz@mordor.com | finger/mail info@ritz.mordor.com OR Mordor International | http://www.mordor.com/ 201/212/718 internet access | Modem: (201)433-7343,(212)843-3451