PC Mother Board Power on Sequence

Laptop no power,laptop repair part-2

Dell  Laptop power on NO-DISPLAY Diagnosis

v According to Dell  support  when Laptop is powered on but you don’t get display then the possible areas of failure are indicated with some beep codes

v  Here im providing the List (for obvius reasons iam not following 1,2,3 order) and possible solutions

Ø 5 Beeps

Solution:

 Remove CMOS Battery ( also called RTC battery) and check voltage of Battery, it should be 3V, if does not show exact value then replace with new one, if it good  then put the battery back in socket , since removal of RTC Battery takes system back to default settings,  go to set up menu and set date and time and other options like boot priority legacy -UEFI mode etc.

Ø 2 Beeps

Solution:

1)      Remove RAM clean it, use eraser to clean the contact points

2)      Clean the DIMM slot ( Memory slot) with IP or Petrol, use Tooth brush

3)      Try with known good  RAM

Ø 8 Beeps

Solution:

1)      Check Display cable Remove and Reseat it

2)      Graphic  Issue (Re flow or Convert to non Graphic)

Ø 7 Beeps

Solution:

1)      Check CPU

2)      Check CPU_PWR ( if no trouble shoot VRM section)

3)       

Ø 1 Beep

Solution:

Re-Program BIOS

Ø 4 Beeps

Solution:

1)      RAM

2)      DIMM Slot

3)      Check Memory Voltage, for DDR3 it is 1.5v and for DDR-L it is 1.35v.( if Low Voltage trouble shoot Memory regulator)

Ø 3 Beeps

1)      PCH

2)      GPU

3)      I/O Controller (KBC)

4)      ON-Board Processor ( If Used)

Solution:

Ø 6 Beeps

Solution:

Main BIOS( also called Syten BIOS or PCH BIOS)

HP Laptop LED Blink codes

This Post will help you to identify issues Related to HP Laptops

courtesy:
http://h20564.www2.hp.com/hpsc/doc/public/display?docId=emr_na-c01732674

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