Re: [LAU] Hard lock-ups plus MOTU UltrLite Mk3

On Sat, May 23, 2009 at 09:50:45PM -0400, Darren Landrum wrote: Ah, good, that reduces the component set to something quite smaller. The things I would consider as cause for that are: 1. dust in the CPU cooling fins, (I take my systems outside and run a vacuum cleaning in reverse, with a thin nozzle, and play the air stream over the various parts of the heatsink), 2. non-rotation or slow rotation of the cooling fans, (if the system has a BIOS sensor display, check that it shows a reasonable rotation of the fan, typical rotation rates are from 1000 to 3000 RPM, in my experience, and is fixable by replacing the fan, or cleaning it) 3. drying out of the thermal conducting grease between the CPU and the heatsink, (I recently had to remove and reapply the grease on a Pentium 4 3GHz desktop at home, symptom was CPU temperature consistently high and random power downs), 4. failing power supply, (I unplug non-essential devices temporarily, such as hard drive, to lower the average power draw, and see if the memtest symptom goes away ... I also check the power supply voltages with a meter), 5. corrosion or other damage to the memory DIMM socket or module, (I wiggle the DIMMs during a memtest, with about the equivalent of up to 200 gram force ... if the memtest result changes in a cycle with my wiggling, I know there's damage), 6. a specific memory DIMM failed, (remove it, see if memtest completes). Oh, and above all remember to use anti-static procedures, and try not to unplug or replug things inside the unit while the power is on. Static discharge damage is particularly annoying because it typically happens months after the static discharge happens. The discharge causes damage which then takes a long time before it begins to make the component fail. So "it works after I zapped it" isn't a reliable method of proving no damage was done.