From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ed W Date: Tue, 26 Oct 2010 09:25:53 +0000 Subject: [lm-sensors] Coretemp misreading? Message-Id: <4CC69EA1.4050501@wildgooses.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lm-sensors@vger.kernel.org Hi, I have a pair of (identical) new supermicro machines and had some significant issues getting accurate temps out of them. Bios updates (betas) have fixed most of them, but I'm finally stuck with the CPU temps reading exceptionally high using the kernel coretemp module Board is the supermicro X8SIE-LN4F. Processor is an intel L3426 (ie the 45W part). Sensors 3.1.2 reads (loaded): coretemp-isa-0000 Adapter: ISA adapter Core 0: +81.0C (high = +94.0C, crit = +100.0C) coretemp-isa-0001 Adapter: ISA adapter Core 1: +79.0C (high = +94.0C, crit = +100.0C) coretemp-isa-0002 Adapter: ISA adapter Core 2: +81.0C (high = +94.0C, crit = +100.0C) coretemp-isa-0003 Adapter: ISA adapter Core 3: +77.0C (high = +94.0C, crit = +100.0C) Idle the temps are around 55-60C There is no bios CPU temp to compare against, all I get is a "Low" reading normally, going up to a "Med" reading when the temps are as above (there is also a "high", but unknown when that kicks in) Additionally there are some temps shown through the sensors module (these were affected by the bios fixes) temp1: +36.0C (high = +60.0C, hyst = +55.0C) sensor = thermistor temp2: +78.5C (high = +95.0C, hyst = +92.0C) sensor = diode temp3: +30.0C (high = +80.0C, hyst = +75.0C) sensor = thermistor The bottom one coincides with the bios "System Temp" and is believed to be the thermistor at the back of the board. Unknown what the other two are. The Temp2 tends to look a little like the average of the CPU temps though? Basic sanity check though. I take the lid off the machine and the heatsink is completely cold at idle and slightly warm under load... I have reseated the heatsink on one of the machines as a sanity check, no difference. Both machines are reporting the same range of temperatures under similar loads. I checked temps using kernel 2.6.32 and 2.6.36 with similar results My best guess is that the CPU temp sensor is mis-reading. However, is this possible? I understand the CPU temp is specified as an inversion from the max value and hence in any case if the observed temp is wrong then the point is still that my "margin" for safety is something like the 94C - 81C = 13C from max temp? This machine needs to last long term, I'm currently a bit worried about the reported temps - can anyone please shed some light on whether this is just a bad reading and should be ignored? Thanks Ed W _______________________________________________ lm-sensors mailing list lm-sensors@lm-sensors.org http://lists.lm-sensors.org/mailman/listinfo/lm-sensors