This article is from the 3b1 computers FAQ, by John B. Bunch with numerous contributions by others.
This symptom crops up in a lot of UNIX PC's. Generally, the machine can be revived with only little fuss. Open the machine down to the motherboard. Carefully reseat all the socketed chips, especially the 68010 CPU. Blow all of the accumulated dust out of the machine (vacuuming is not recommended due to the possibility of static discharge). 7 times out of 10 the machine will boot afterwards. If the machine still doesn't boot, it could be something more serious. Check with the ASCRC on how you can go about getting the machine repaired.
 
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