From owner-freebsd-questions Tue Apr 6 20: 5:42 1999 Delivered-To: freebsd-questions@freebsd.org Received: from finch-post-10.mail.demon.net (finch-post-10.mail.demon.net [194.217.242.38]) by hub.freebsd.org (Postfix) with ESMTP id 0EA94156F6 for ; Tue, 6 Apr 1999 20:05:35 -0700 (PDT) (envelope-from marko@uk.radan.com) Received: from [158.152.75.22] (helo=uk.radan.com) by finch-post-10.mail.demon.net with smtp (Exim 2.12 #1) id 10Uick-00026Q-0A; Wed, 7 Apr 1999 03:03:31 +0000 Organisation: Radan Computational Ltd., Bath, UK. Phone: +44-1225-320320 Fax: +44-1225-320311 Received: from marder-1. (rasnt-1 [193.114.228.211]) by uk.radan.com (8.6.10/8.6.10) with ESMTP id EAA00829; Wed, 7 Apr 1999 04:03:01 +0100 Received: (from marko@localhost) by marder-1. (8.9.2/8.8.8) id EAA04795; Wed, 7 Apr 1999 04:01:13 +0100 (BST) (envelope-from marko) Date: Wed, 7 Apr 1999 04:01:13 +0100 From: Mark Ovens To: Greg Lehey Cc: Darren Pilgrim , "Dragon Knight ][" , FreeBSD Questions Subject: Re: K6-2/333, was: Re: Debug kernel by default (was: System sizewith -g) Message-ID: <19990407040113.F4453@marder-1.localhost> References: <3709569A.70EEC38A@uswest.net> <37097B00.2186EB92@dtgnet.com> <3709EDEB.BE17A2E8@uswest.net> <19990407025433.C4453@marder-1.localhost> <19990407114602.Z2142@lemis.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.95.3i In-Reply-To: <19990407114602.Z2142@lemis.com>; from Greg Lehey on Wed, Apr 07, 1999 at 11:46:02AM +0930 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Wed, Apr 07, 1999 at 11:46:02AM +0930, Greg Lehey wrote: > On Wednesday, 7 April 1999 at 2:54:33 +0100, Mark Ovens wrote: > > > > As the person who effectively started all this discussion about > > bus speeds and multipliers I just want to thank all the contributors > > to this thread. I now have a better understanding of how it all > > works. The fundamental misunderstanding I had was that the CPU > > itself did the mutliplication and that the m/b jumpers simply "told" > > the CPU what multiple of the bus speed to use. > > It does. But there are various parts of the CPU. The part which > creates the CPU internal clock is just a bit of relatively simple > hardwired logic. > Just when you thought it was all over.....:-) So my understanding was correct. Other posters have suggested that the m/b supplies the multiplied clock frequency to the CPU and therefore the it *can't* ignore it. However, whilst 95MHx & 3.5X is equivalent to 66MHz & 5X, if the CPU doesn't understand "run at 5X" then it may be running at an arbitrary speed (3.5X bus?). This all started when you said that you had noticed no (significant) performance increase from a K6/233 to a K6-2/333. Whilst I'm not disputing with you that an old HD will adversely affect performance on disk I/O intensive work such as compiling I would expect a noticeable performance increase overall, especially with 160MB of RAM. This is what prompted me to ask if, whilst mathematically equivalent, 95MHz & 3.5X was the same as 66MHz & 5X in practice and if it isn't then that could explain the lack of performance gain. > > I guess that AMD only state 95MHz & 3.5X, and not 66MHz & 5X, > > because it gives the maximum absolute performance of the chip as > > the CPU <==> memory is running at its highest speed. > > Correct. And in fact I'd guess that you could probably choose 100 > MHz. I've been running this chip for over a week now, and it seems to > be fine, so I suppose it's time to start experimenting with > overclocking. > > Greg > -- > When replying to this message, please copy the original recipients. > For more information, see http://www.lemis.com/questions.html > See complete headers for address, home page and phone numbers > finger grog@lemis.com for PGP public key > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-questions" in the body of the message > -- FreeBSD - The Power To Serve http://www.freebsd.org My Webpage http://www.users.globalnet.co.uk/~markov _______________________________________________________________ Mark Ovens, CNC Apps Engineer, Radan Computational Ltd. Bath UK CAD/CAM solutions for Sheetmetal Working Industry mailto:marko@uk.radan.com http://www.radan.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message