From owner-freebsd-questions Mon Nov 12 22:25:19 2001 Delivered-To: freebsd-questions@freebsd.org Received: from hotmail.com (f106.law11.hotmail.com [64.4.17.106]) by hub.freebsd.org (Postfix) with ESMTP id 707F337B416 for ; Mon, 12 Nov 2001 22:25:16 -0800 (PST) Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Mon, 12 Nov 2001 22:25:16 -0800 Received: from 24.116.158.21 by lw11fd.law11.hotmail.msn.com with HTTP; Tue, 13 Nov 2001 06:25:15 GMT X-Originating-IP: [24.116.158.21] From: "Charles Burns" To: aobradovic@ballantyneinc.com Cc: questions@freebsd.org Subject: Re: overclocking and freebsd Date: Mon, 12 Nov 2001 23:25:15 -0700 Mime-Version: 1.0 Content-Type: text/plain; format=flowed Message-ID: X-OriginalArrivalTime: 13 Nov 2001 06:25:16.0173 (UTC) FILETIME=[F576D3D0:01C16C0B] Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG >Alex Obradovic types: > > Has anyone been able to overclock successfully with FreeBSD? I was > > running my Pentium 3-850 at 1 Gghz for a year with Win 2K. After I > > scrapped windows and installed FreeBSD, I had to go down to 850 since > > my system would have lots of disk issues, and it would not boot. > > > > Any overclockers out there? > >While there are some, the general consensus seems to be that FreeBSD >pushes the hardware more than Windows, meaning that the overclocking >levels that work are much lower - typically around 5%, as opposed to >the nearly 20% you got. Since turning off overclocking and trying >again is the suggested response to any problems on an overclocked >system, I don't bother. This is more to the original poster than to Mike, but I don't have the original post anymore. I had an Athlon 500 "classic" overclocked to 800MHz in FreeBSD and Linux, but it would only do 750 in Windows, so I guess it depends on a number of factors. What I usually do when I overclock, which I have not done for some time, is to clock the system as high as it will go while still perfectly running extensive stress tests (like a build world while running 2 copies of SETI@HOME) for an extended period of time. Then I clock it down by 1/2 a multiplier. I also do the stress tests with a stock heatsink and then get a nice big one from 1coolpc or somewhere. If your system would not clock as high in FreeBSD, it was not stable at the "windows" speed. Windows may be less likely to care if it flips a bit, but you never know when it will flip the wrong bit--be sure to run it at a speed that it can run well. Some chips are tested as capable of running higher speeds by the manufacturer, but are marked down due to greater demand for the slower, cheaper chips. Some chips that are marked as being able to run XX MHz really mean it. Some chips, like the ill-fated and recalled 1st try Intel Pentium3 1.13GHz chip can't even run stable at the rated clockspeed. Example-- The Athlon 500 was marked on the casing as a 500 but the core was marked as a 600MHz chip. Anymore, fast chips are so cheap that I really don't see much point in overclocking unless the fastest available chips aren't fast enough, but usually when a system needs that much speed, the system is important enough that stability takes top priority over a 10%-15% real world performance gain. That said, most of the better AthlonXP cores can run at 1666MHz without any special cooling and 1800MHz with water cooling. The old Athlon T-bird 1400 core can run at 1bout 1800MHz with the Kryotech case, and probably with a peltier+water cooler+lots of fans combo--but is it really worth the risk and cost? Charles Burns _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message