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<TITLE>Strange hardware (was Re: custom hardware (was: Xbox clusters?))</TITLE>
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<BR><FONT SIZE=2>Yep, seen this problem many times in our computer hire range of Windows2000Pro machines. The strange thing is that we only see this on Slot 1 Pentium II machines with various model motherboards. All our Pentium III range are socket 370 and no problems. So we came to a feeling that the problem was the way in which the Slot1 Pentium II sits on the motherboard. After months of clients returning equipment to base under warranty, we issued instruction on how to open the case and remove and re seat the PentiumII Slot 1 processor package. The machines then boot every time after switch on. </FONT></P>
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<BR><FONT SIZE=2>How many of you having this problem have it with the slot 1 Pentium II and slot 2 Pentium III processors in your clusters? I bet none of you have it with a socket 370 or other "flat" socket type of CPU package. We're fortunate that our development cluster is based on Pentium 233MHz MMX "old" ex-hire equipment so we don't have this problem on the cluster. Yet! </FONT></P>
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<BR><FONT SIZE=2>Regards, </FONT>
<BR><FONT SIZE=2> Mark. </FONT>
<BR><FONT SIZE=2> </FONT>
<BR><FONT SIZE=2>-----Original Message----- </FONT>
<BR><FONT SIZE=2>From: Felix Rauch [SMTP:rauch@inf.ethz.ch] </FONT>
<BR><FONT SIZE=2>Sent: Thursday 29 November 2001 12:00 </FONT>
<BR><FONT SIZE=2>To: beowulf@beowulf.org </FONT>
<BR><FONT SIZE=2>Subject: Strange hardware (was Re: custom hardware (was: Xbox clusters?)) </FONT>
<BR><FONT SIZE=2> </FONT>
<BR><FONT SIZE=2>On Thu, 29 Nov 2001, Daniel Pfenniger wrote: </FONT>
<BR><FONT SIZE=2>> I have seen similar strange behavior of some boxes in a set of 66's, </FONT>
<BR><FONT SIZE=2>> and the way </FONT>
<BR><FONT SIZE=2>to restart is also rather odd. </FONT>
<BR><FONT SIZE=2>[...] </FONT>
<BR><FONT SIZE=2> </FONT>
<BR><FONT SIZE=2>We recently had strange problems with a Dell-Box which has been </FONT>
<BR><FONT SIZE=2>working without problems for </FONT>
<BR><FONT SIZE=2>several years in our small research </FONT>
<BR><FONT SIZE=2>cluster. It's a dual PII 400 MHz box, but suddenly the Linux kernel </FONT>
<BR><FONT SIZE=2>was unable to start the second </FONT>
<BR><FONT SIZE=2>CPU. It could see the second CPU, but </FONT>
<BR><FONT SIZE=2>when it tried to start it up during boot, it got a timeout and so </FONT>
<BR><FONT SIZE=2>continued with only one CPU. </FONT>
<BR><FONT SIZE=2> </FONT>
<BR><FONT SIZE=2>So </FONT>
<BR><FONT SIZE=2>we though that one of the CPUs died and replaced both CPUs. Still </FONT>
<BR><FONT SIZE=2>the same problem. Next we replaced the motherboard (including the </FONT>
<BR><FONT SIZE=2>power </FONT>
<BR><FONT SIZE=2>suply). Still the same problem. Maybe the disk corrupted the </FONT>
<BR><FONT SIZE=2>kernel, so we installed a fresh version of the same kernel onto the </FONT>
<BR><FONT SIZE=2>box. </FONT>
<BR><FONT SIZE=2>Still the same problem. Only after physically replacing the SCSI </FONT>
<BR><FONT SIZE=2>hard disk everything was working properly again. </FONT>
<BR><FONT SIZE=2> </FONT>
<BR><FONT SIZE=2>We are still wondering </FONT>
<BR><FONT SIZE=2>why a disk could cause a CPU to timeout during </FONT>
<BR><FONT SIZE=2>boot... </FONT>
<BR><FONT SIZE=2> </FONT>
<BR><FONT SIZE=2>- Felix </FONT>
<BR><FONT SIZE=2>-- </FONT>
<BR><FONT SIZE=2>Felix Rauch | Email: rauch@inf.ethz.ch </FONT>
<BR><FONT SIZE=2>Institute </FONT>
<BR><FONT SIZE=2>for Computer Systems | Homepage: <A HREF="http://www.cs.inf.ethz.ch/~rauch/" TARGET="_blank">http://www.cs.inf.ethz.ch/~rauch/</A> </FONT>
<BR><FONT SIZE=2>ETH Zentrum / RZ H18 | Phone: ++41 1 632 7489 </FONT>
<BR><FONT SIZE=2>CH </FONT>
<BR><FONT SIZE=2>- 8092 Zuerich / Switzerland | Fax: ++41 1 632 1307 </FONT>
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