hp 255-g1 blinking continuously

[gcomputers]

Hi i m working with this hp that when i press power button blinking led of power button continuously and no fan activity .
CPU is EM1 , flashed bios the same reflowed atichip and cpu no change .
resistance on coils of cpu is 10 ohms , 81 ohm and 150 ohm ,
resistance of chipset FCH ati is 73ohm.

What do you think is fault of CPU ?
Any suggestion ?

[gcomputers]

Re: hp 255-g1 blinking continuously

any suggestion please?

[LP_tekh]

Re: hp 255-g1 blinking continuously

Could be the 128 pin ic (winbond). power and fan are connected to it.

[dj_ricoh]

Re: hp 255-g1 blinking continuously

if CPU its bad then on memory socket pin 2 and 4 if i recall will show activity on scope.
if for some reason there is no activity there with memory then the CPU its bad.

now on the other side did yo check for corrosion and bad solder?

really close you need to look and how was the thermal compound? hard?

[gcomputers]

Re: hp 255-g1 blinking continuously

hi thanks for yours reply, i measured pin 2 of memory socket is ground , pin 4 when i power on have 240mv.
When i hold down the power button does not turn off, continues to blink .
Any suggestion?

[gcomputers]

Re: hp 255-g1 blinking continuously

if CPU its bad then on memory socket pin 2 and 4 if i recall will show activity on scope.
if for some reason there is no activity there with memory then the CPU its bad.

now on the other side did yo check for corrosion and bad solder?

really close you need to look and how was the thermal compound? hard?

thermal compound its ok (not hard)

[gcomputers]

Re: hp 255-g1 blinking continuously

ic 128 pin is ITE it8517e can i replace with it8518e ?

[gcomputers]

Re: hp 255-g1 blinking continuously

Today i worked on another hp 255 with the same problem POWER BUTTON ONE BLINK BLINKING CONTINUOUSLY .
THis model is UMA 6050a2493101-mb-a02 flashed bios no change . CPU is not integrated on bord but i don t have another to test it.

<<<<<some experience with this model >>>>>

[LP_tekh]

Re: hp 255-g1 blinking continuously

ic 128 pin is ITE it8517e can i replace with it8518e ?

You can try to replace it, see what happen.

[LP_tekh]

Re: hp 255-g1 blinking continuously

Today i worked on another hp 255 with the same problem POWER BUTTON ONE BLINK BLINKING CONTINUOUSLY .
THis model is UMA 6050a2493101-mb-a02 flashed bios no change . CPU is not integrated on bord but i don t have another to test it.

<<<<<some experience with this model >>>>>

Try to flash the ec chip, get it from other board if they are the same, just to find out.