Cpu Power on But motherboard no display | Repair VRM Circuit

No display when the motherboard is powered on. And the CPU is not in normal heat. The VRM circuit is checked.

 Motherboard Power on cpu fan Run okay , But No display or Cpu Not Heating 

VRM Circuit Diagram layout
VRM Circuit Block Diagram

 

  • First will check Mosfet logic signal on the source and drain (TP1 Point). If the logic signal  available . Still the CPU is not normal heat. then Check TP2 point connected  capacitor and Micro processor.  
  •  If TP1 is not logic at point. Of the T-gate Mosfet Drain to check on the positive supply 12v. Drain getting the positive supply, the Mosfet gate to check the positive signal or logic. Getting gate logic. Still, the logic can not point TP1. The T-Gate, B-Gate Mosfet  to check for open.
  •  At the Gate of the Mosfet is not getting positive signals or logic. VRM chip on the VCC pin  5v/12v will check supply. VCC pin is not supplied, then the pin will get a check for open 0ohm resistance. If the resistance is open again. The IC is bad. replace Vrm ic .
  • On the VCC pin is getting positive supply. Still T-Gate, B-Gate pins is not getting the signal at the Ic .Check all Signal on Vrm Chip.
  • The shutdown pin to check the shutdown signal .
    High signal to check on the SS pin.
    Check the enable signal to the enable pin.
    if low singal available on SS pin . Check for shorting to capacitor is pin path .
    If the shutdown is not getting a signal. CPU socket fitted correctly to the CPU socket.

    If the shutdown, enable the SS signal is correct. Still T-Gate, B-Gate is not getting the signal at the gate pins. Vrm chip is Faulty. Replace Chip 


Note : Computer Hanging Problem
The root cause computer to hang.
  Computer hardware, software or viruses
The hard disk will be separate from the motherboard. The computer hangs after the hard disk is separate. This problem is the CPU or VRM circuit.
After separating from the motherboard to the hard disk, the computer does not hang. This means the operating software malfunction is caused by viruses and hard disk  Bad sector. 

 Computer Display Ok , But Computer Restart Again and again .

 The display is getting the power on. But the computer is restarted again and again . then check TP2 Point connected Capacitor For short or bad . replace all capacitor its path. 

NOTE:- 
  • Computer also Restart if hard disk infected to computer viruses OR short Capacitors  
  • If system Start Pressing on/off botton again and again .then replaced Capacitor on Connected TP2 point  

repair vrm circuit




vrm circuit diagram

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