On the Dell support site, for your system, the motherboard manual will help decode the meaning. Or phone Dell’s support with the info. If there are no LEDs, a computer repair company could use a ‘POST card’ to do the diagnostics. It is likely deteriorated thermal paste, a faulty fan, overheating damage, or ‘Tin spikes’, basically rust, in the main chipset. Budget for replacing the machine. Unless under warranty replacing parts could go on for a while. Any of these are possible and many other echoes may influence the here and now. I might ask my patient.
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