A Strange Happenstance

[Bob Farlow]

Last night I had a frightening experience. My computer was in hibernate mode as I usually do before going to bed. However, I decided to check my email once again. I powered it up and was shocked when all of a sudden it froze up. No mouse control, scrolling, etc. My first reaction - "Oh no, a virus, or maybe a power supply going south". Tried booting to safe mode. No luck. Same symptom. Thought maybe the hard drive was failing, but ruled that out since it was checked with the manufacturer's diagnostic software only a couple of weeks ago, and no problems were reported. Checked the CPU fan and power supply fan. All ok. So, what's the problem I thought. While I was sitting there staring into the opened chassis wondering what's going on, I noticed a small piece of black plastic laying in the bottom of the chassis. I picked it up and examined it carefully. Well, the only black plastic inside the chassis is the CPU fan and heatsink mounting hardware. Upon further investigation, I found one of the four legs of the fan and heatsink assembly had broken off. This let the heatsink cock to one side, and was not making proper contact with the CPU. So, what was happening was the heat being generated by the CPU was not being dissipated properly, causing the CPU to overheat and protect itself by shutting down all operations (freeze up). Super Glue to the rescue. Reattached the broken plastic leg, and all returned to normal operation. I now have Everest Ultimate installed, which shows CPU temperature, fan speed, core voltage, etc. as icons in the tray, since I need to keep a careful watch over things in case the super glue trick fails. But, for now (knock-on-wood) all is honky-dory.

[Wiz Feinberg]

I have seen this on a couple of older HP computers I serviced. They use a plastic frame to hold the heatsink clips in place. When one of the clips broke the heatsink pulled up on the corner, causing thermal runaway and instant shutdown.

A phone call to HP sales produced no solution, other than "send it back to us, prepaid freight." I also ended up super-gluing it back together. What a shame these OEM builders won't sell their customers replacement mounting brackets!