From owner-freebsd-stable Thu Dec 12 21: 8:34 2002 Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id C4BD537B404 for ; Thu, 12 Dec 2002 21:08:32 -0800 (PST) Received: from smtp-3.paradise.net.nz (smtp-3a.paradise.net.nz [202.0.32.196]) by mx1.FreeBSD.org (Postfix) with ESMTP id BB28043EB2 for ; Thu, 12 Dec 2002 21:08:31 -0800 (PST) (envelope-from james.pole@paradise.net.nz) Received: from 203-79-102-242.tnt14.paradise.net.nz (203-79-102-242.tnt14.paradise.net.nz [203.79.102.242]) by smtp-3.paradise.net.nz (Postfix) with ESMTP id 6BC75AE330; Fri, 13 Dec 2002 18:08:24 +1300 (NZDT) Subject: Re: Cyrix CPUs, was: Re: Repeatable crash from nautilus2 From: James Pole To: Charles Swiger Cc: freebsd-stable@FreeBSD.ORG In-Reply-To: <004901c2a25c$0c381c50$0301a8c0@prime> References: <20021213021012.61714.qmail@web40303.mail.yahoo.com> <004901c2a25c$0c381c50$0301a8c0@prime> Content-Type: text/plain Organization: Message-Id: <1039756076.12023.5.camel@localhost> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.2.0 Date: 13 Dec 2002 18:07:56 +1300 Content-Transfer-Encoding: 7bit Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Fri, 2002-12-13 at 16:58, Charles Swiger wrote: > Rhett Monteg Hollander wrote: > [ ... ] > > What Cyrix CPU? And what OS'es? And maybe vice versa? > > I do remember hard issues with WinNT 3.51 and original > > Win'95 when running on Cyrix 5x86\6x86 or NexGen > > Nx586. > > # CPU_BTB_EN enables branch target buffer on Cyrix 5x86 (NOTE 1). > # > # CPU_DIRECT_MAPPED_CACHE sets L1 cache of Cyrix 486DLC CPU in direct > # mapped mode. Default is 2-way set associative mode. > # > # CPU_CYRIX_NO_LOCK enables weak locking for the entire address space > # of Cyrix 6x86 and 6x86MX CPUs by setting the NO_LOCK bit of CCR1. > # Otherwise, the NO_LOCK bit of CCR1 is cleared. (NOTE 3) > [ ... ] > # NOTE 1: The options, CPU_BTB_EN, CPU_LOOP_EN, CPU_IORT, > # CPU_LOOP_EN and CPU_RSTK_EN should not be used because of CPU bugs. > # These options may crash your system. > # > # NOTE 2: If CYRIX_CACHE_REALLY_WORKS is not set, CPU cache is enabled > # in write-through mode when revision < 2.7. If revision of Cyrix > # 6x86 >= 2.7, CPU cache is always enabled in write-back mode. > # > # NOTE 3: This option may cause failures for software that requires > # locked cycles in order to operate correctly. > > Yum. Sounds tasty. Indeed it does. Intel and AMD, despite having produced processors for many years, still havn't achieved the "fame" that Cyrix has achieved in the LINT file. I think the fact Cyrix isn't very popular these days, compared to Intel/AMD processors says a lot about the quality of their processors back in the Pentium/586 days. Nowdays people use Intel/AMD processors and to date I havn't come across any serious problems with those processors. I'm not saying they don't have problems, but Intel/AMD are often willing to replace CPUs with bugs (such as that floating point pug that occured in the Intel Pentium in the mid-1990's) and many of the bugs are so simple they are solved by a simple software workaround (eg Intel's F00F bug -- almost every OS including FreeBSD includes the workaround). - James To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message