From owner-freebsd-hackers Sat Aug 2 00:54:00 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.5/8.8.5) id AAA09859 for hackers-outgoing; Sat, 2 Aug 1997 00:54:00 -0700 (PDT) Received: from bugs.us.dell.com (bugs.us.dell.com [143.166.169.147]) by hub.freebsd.org (8.8.5/8.8.5) with SMTP id AAA09854 for ; Sat, 2 Aug 1997 00:53:56 -0700 (PDT) Received: from ant.us.dell.com (ant.us.dell.com [198.64.66.34]) by bugs.us.dell.com (8.6.12/8.6.12) with SMTP id CAA27453; Sat, 2 Aug 1997 02:51:36 -0500 Message-Id: <3.0.2.32.19970802023853.0069c4c4@bugs.us.dell.com> X-Sender: tony@bugs.us.dell.com X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.2 (32) Date: Sat, 02 Aug 1997 02:38:53 -0500 To: Terry Lambert , brianc@milkyway.com (Brian Campbell) From: Tony Overfield Subject: Re: Pentium II? Cc: hackers@FreeBSD.ORG In-Reply-To: <199707302054.NAA05832@phaeton.artisoft.com> References: <19970730144420.16698@milkyway.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-freebsd-hackers@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk At 01:54 PM 7/30/97 -0700, Terry Lambert wrote: >> > My 486 DX-50 still beats the snot of of a P5 DX/2-66, and is >> > more than fast enough (EISA bus overclocked to 50MHz) to handle >> > a lot of stuff that early P5 machines couldn't. >> >> Hmmm ... Never heard of a P5 DX/2-66 ;-) > >Dell was selling them. This is wrong! Dell sold no such thing as a "P5 DX/2-66"! >This was back when they were using the >Saturn I chipset, which did not have DMA writeback notification >connected from the macrocell (missing trace). Due to that bug, that version of the Saturn chipset does not support write-back L2 caching and it is therefore configured by the BIOS to use the L2 cache in write-through mode, though the L1 cache is always write-back. The missing trace is not used or needed when the L2 cache is in write-through mode. >Clock-doubled 66 MHz Pentiums were at one time common, before >CPU fans became common. Hmm, they weren't common enough for me to have ever heard of them before. >Dell also had 60MHz non-doubled chips >available before the doubled 66's were available. Well, of course the 66 MHz chips were available after the 60 MHz chips were, but they weren't "doubled." >The non-doubled >60's kicked butt over the doubled 66's for anything I/O bound. They probably would have, had the "doubled 66's" ever existed. >Just as my 486/50 kicks butt over the same chips. I doubt this, unless you're "stacking the deck" in some perverse way, or you're simply dreaming. - Tony