What computer need different voltages at mother board like 1.5V 5V 12V etc??
Pretty much all of them. It may be that there are some for embedded systems that use a single voltage, but anything for a PC will use several voltages.
PSU standards and history .
i have open the processor it was dissipating a lot of heat, why?
small few inches more than heater or same.
I SERIOUSLY doubt you have "opened the processor". More likely you have just opened the computer. The processor is the CPU chip and you can't "open" it without destroying it.
Electrical components get hot and computers have particularly dense packing so there can be a lot of heat in a small space.
The processor is lock based there are lot of pins
Yes. So what is your point? What does "lock based" mean?
ok i got it there may be different circuit operating...
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