PC borard ASUS P7P55D LE - not start

[ktmmotocross]

Hello.
Have this PC board AsusP7P55D LE rev. 1.10G - that not start

Post card show no clock just still light RSTJ led

Im new to PC board repair. Have somebody clue what can i check first?

I checked all power mosfets but everyone shows some good voltage

[on/off]

Re: PC borard ASUS P7P55D LE - not start

Boardview:

[dj_ricoh]

Re: PC borard ASUS P7P55D LE - not start

Well that is easy. Start tracking the voltage from dc in.
Somewhere there is a short or something doesn't output.
There needs to be 3.3v always and 5v.

Even in diagram you will see them with 3.3alw or something similar.
If those voltages are missing the you don't have power button voltage(3.3v)
Bios voltage(3.3v)
Reflash the bios (sometimes it makes the laptop dead)
Take the charging ic from diagram and measure all the voltage and write them here.

[ktmmotocross]

Re: PC borard ASUS P7P55D LE - not start

thanks, but i dont have boardwiever app for this kind of files
can u please upload it?

[ktmmotocross]

Re: PC borard ASUS P7P55D LE - not start

Well that is easy. Start tracking the voltage from dc in.
Somewhere there is a short or something doesn't output.
There needs to be 3.3v always and 5v.

Even in diagram you will see them with 3.3alw or something similar.
If those voltages are missing the you don't have power button voltage(3.3v)
Bios voltage(3.3v)
Reflash the bios (sometimes it makes the laptop dead)
Take the charging ic from diagram and measure all the voltage and write them here.

power button and alw voltages are present. the board starts after switching power button, all mosfets have voltages presents, but RSTJ light on postcard not shut down like normal

dont have diagram for this board. i found it on vinafix. but dont have registration on it

[ktmmotocross]

Re: PC borard ASUS P7P55D LE - not start

power button and alw voltages are present. the board starts after switching power button, all mosfets have voltages presents, but RSTJ light on postcard not shut down like normal

dont have diagram for this board. i found it on vinafix. but dont have registration on it

And dont have CLK light blinking like normal

have anybody diagram or bios dump?

[ktmmotocross]

Re: PC borard ASUS P7P55D LE - not start

Damn guys what could be wrong?

i smell something bad so i remove processor, touch capacitors around him and got REALLY BAD BURN to my finger. i mark that capacitors that got really hot

Do u think that thats capacitors got little short? because voltage was about 1.1V and slowly drops to 0.9 and coils got heat

[dj_ricoh]

Re: PC borard ASUS P7P55D LE - not start

Diode mode each mosfet,lift coils, lift caps out

[ktmmotocross]

Re: PC borard ASUS P7P55D LE - not start

Solved

It was real pain in the ass and cost me about 2 hours to replace that 9 caps but it worth that.

replaced caps for caps from GPU im now repairing and board comes to life

[dj_ricoh]

Re: PC borard ASUS P7P55D LE - not start

Solved

It was real pain in the ass and cost me about 2 hours to replace that 9 caps but it worth that.

replaced caps for caps from GPU im now repairing and board comes to life

Fantastic!
Can you confirm those polymer caps could go shorted?
Do you have esr meter or capacity?
Thanks

[ktmmotocross]

Re: PC borard ASUS P7P55D LE - not start

i have low budget components meter like this

https://www.aliexpress.com/item/High...AbTest=ae803_3

Its great because it can identify many components/mosfets, diodes, caps, esr meter, transistors/ . its built in esr meter cannot identify component - that caps. it cannot identify caps if it is bolded and are sure bad

i think that caps have so high resistance that act as a load, because it burn even without processor

[george_gpu]

Re: PC borard ASUS P7P55D LE - not start

Solved

It was real pain in the ass and cost me about 2 hours to replace that 9 caps but it worth that.

replaced caps for caps from GPU im now repairing and board comes to life

hi, do you remember the value of this capacitor
all has the same value?

[joshmonger]

Re: PC borard ASUS P7P55D LE - not start

Solved

It was real pain in the ass and cost me about 2 hours to replace that 9 caps but it worth that.

replaced caps for caps from GPU im now repairing and board comes to life

I wonder do you have a list or a recommendation for what the caps are and which ones to purchase to replace?