The big question is, are the CPU's a matched set? Let Me explain. Each CPU must the the same ""Stepping" "(stp)"" in your case... (stp) etc... SL6VP 3.06 GHz 533 MHz 0.13 micron D1 512 KB 604 pin SL6GH 3.06 GHz 533 MHz 0.13 micron C1 512 KB 604 pin SL6RR 3.06 GHz 533 MHz 0.13 micron C1 512 KB 604 pin SL6YR 3.06 GHz 533 MHz 0.13 micron D1 512 KB 604 pin In other words; Each CPU must be from the same microcode version. The stepping is on the CPU itself. You are lucky you didn't fry the CPU's, if the stepping is off. This is the Intel site with the information you need to check. http://processorfinder.intel.com/scripts/default.asp?CHRID=528 Sam. Quoting Randy Clarksean <rclark at lakesplus.com>: > I have had some ongoing issues with a set of dual 3.06 533MHz 512K Xeon > CPUs. I have just bought a new set of components to build around these > CPUs that I had in my possession. > > ASUS PC-Deluxe MB > 4 GB RAM > Dual CPUs (XEON, 3.06 533 MHz 512K) > FC5 installed OS with raid, LVM > > Issue: I built the system, finally have the hard drives configured as I > want, now ... the system just starts to hang while away, or crashes > along the way. > > A couple of times recently though, during boot I have gotten some CPU > warnings ... similar to what I have seen in the past. In addition, the > system will just seem to lock up on occasion. The CPU checks that are > run at boot time ... shouldn't those errors show up more often, or does > the phase of the moon sorta thing have to be just right for a crash like > that to occur? > > What is odd though, I ran a couple copies of this heavily intensive CPU > application (mprime I think it was) ... ran for over 12 hours ... with > both CPUs buried - no errors, but then some time later the system just > crashed heavily. > > Things I have already considered: > > - over heated CPUs ... brand new coolers, used thermal grease - bios > monitoring shows temps to be reasonable - at least when I can get in to > check on them. > - power supply ... bought decent brand, not cheap one. > - UPS ... plugged into APC 420 SmartUPS (no indication of overload), > shares this with another tower. > > Other thoughts and suggestions? I NEED this system up and running soon > for work (heavy CPU related activities). > > Thanks in advance. > > Randy > > p.s. Any suggestions on a good location to purchase a matched set of > these CPUs? I have been looking on the web - pricewatch - and they only > list single CPUs. These are slightly older technology ... so tougher to > locate. > > > _______________________________________________ > TCLUG Mailing List - Minneapolis/St. Paul, Minnesota > tclug-list at mn-linux.org > http://mailman.mn-linux.org/mailman/listinfo/tclug-list >