PC hardware--CPU & Motherboard & RAM/System hardware problem, Inactive I/O



There is a problem with my desktop.
 System got shut down with a sound & the message "System shut down due to Thermal event overheating". I tried to start a couple of times, but it didn't start. So, I separated the processor from the heat-sink and applied "process cooling thermal paste".

Now the system runs but, I/O devices are not working (inactive). That is, monitor has no display (monitor light blinks), the keyboard's & the mouse's (optical) lights blinks for a split second and turns inactive. At this point, the CMOS battery is also replaced with the new one. Now even after repeated attempts to start the system, the problem still persists.

The system automatically gets power ON and runs directly when the system is connected to the power plug, even without pressing the power button on the CPU cabinet. The technician says, this should not happen.
The SMPS power plug (that connects the motherboard slot "PWR") turned dark a bit (like burn, only the plug).
The technician says there must be a problem with SMPS or the motherboard.

I couldn't able to find the actual problem.  
Kindly, guide me to the solution.


Hi Sumazu,

I would say that most likely the CPU is toasted. A thermal shutdown is a protection for the CPU to avoid the silicon chip metldown, but it might have happened to late for yours.
The technician is right, in ATX motherboards the CPU and the motherboard controls the power supply turn on and off.If the power is applied without pressing the power button in the front, most likely the CPU or the motherboard (or both) are not working properly.


PC hardware--CPU & Motherboard & RAM

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Ricardo Agudelo


any question on networking area,specially if it`s about Windows based networks. Also, as we do some software and hardware testing here,we can provide some help on the PC problems and repair. In PC communications and Internet access and use. Electronic Engineer,Experience 18 years in telecommunications, control, computers and networks

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