From owner-freebsd-isp Thu Jul 12 14:50:18 2001 Delivered-To: freebsd-isp@freebsd.org Received: from imo-r03.mx.aol.com (imo-r03.mx.aol.com [152.163.225.99]) by hub.freebsd.org (Postfix) with ESMTP id B752837B403 for ; Thu, 12 Jul 2001 14:50:13 -0700 (PDT) (envelope-from Bsdguru@aol.com) Received: from Bsdguru@aol.com by imo-r03.mx.aol.com (mail_out_v31.7.) id x.da.8f012a9 (4240); Thu, 12 Jul 2001 17:50:08 -0400 (EDT) From: Bsdguru@aol.com Message-ID: Date: Thu, 12 Jul 2001 17:50:08 EDT Subject: Re: Intel ISP1100 or similar 1U experience with 4.3 stable To: dg@root.com, isp@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Windows sub 139 Sender: owner-freebsd-isp@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org In a message dated 07/12/2001 2:07:02 PM Eastern Daylight Time, dg@root.com writes: > >There is less than 1" of space above the cpu in a 1U unit, which doesnt > leave > >enough space for an approproate heat-sink and fan for high Mhz cpu. Yes > they > >will run, and may never fail, but they are not as reliable as 2U units > which > >allow for a more appropriate heat sink and larger fans. > > Uhh, that just isn't true. It's true that _most_ low profile CPU coolers > will not cool adequately, but certainly not all of them. There are some that > are large but not tall that have a powerful fan and are made partly or > completely of copper that do a fine job of cooling. CPUs in our 1U systems, > for example, run worst case about 20C above ambient temperature, usually > less than 10C above - i.e. about 35C, which is well below the 70C thermal > requirement of the 1GHz FCPGA PIII and fairly close to the performace of the > large aluminum heat sink that Intel provides with the boxed processor. > Firstly, we are talking about dual systems, or at least my original post was. Even on the slimist fan, the clearance above the fan is too small, 1/8 to 1/4" usually. Its not enough space, no matter how powerful the fan. You'll have hot spots, particularly near the cpus, which can cause failures over time. Are you really arguing with me that a 2U enclosure is more reliable and offers better cooling, or only that its possible to use a 1U (or in dgs case are you just trying to justify your product...i suspect you dont have a 2U solution to offer)? Im not sure what is wrong with you people. Very few people cant spare the extra 2" of space,and the result is more reliable, which was and is my point. There is zero question that 2U offers better cooling than 1U, so what exactly are all of you home-spun "engineers" trying to say? B To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-isp" in the body of the message