|Your power supply on the emachines computer was probably damaged by a power spike or power surge. It's probably a BESTEC one, and they're more likely to fail in any case than other power supply brands.|
If one of your other computers is a desktop computer with a standard sized power supply with a capacity the same or more than the one in the emachines computer (watts output) , a standard sized power supply will probably fit in the emachines case - remove it and try hooking it up to the emachines system. (If the other power supply is not standard sized but has enough capacity, try propping it up beside the case and hooking it up anyway). The chances are pretty good that the emachines computer will then work fine. If so, get another power supply for the emachines computer when you have the bucks to spare.
More info about BESTEC power supplies, the standard power supply size, and what you need to know about a replacement.
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