ICHILL Geforce 980 TI Air Boss repair

[Sci666]

hello

i got some average to good soldering skills but i dont have many experience with measuring graphics cards (but i got a realative good multimeter and a hot air station ... unfortunately no IR station until now ;-) )

i had a ichill GTX 980 TI.   the fans spins but no picture.

no optical damage or burn marks on any parts.   no part gets warm if its powered up and the GPU stays cold too !

measuring input and output of some parts seems to be good ... all necessary inputs got 12V or 5 volts but it stops at the coils ... all of them 0 Volts output ....    the middle ones beeps to ground in the beep mode

see picture. do you need some more informations ?

i dont really know how to go on to find the problem because i dont know the interaction between all these parts.


can you give me a hint what i can measure next to identify the faulty part ?

 
so questions,
 1)
why is there no voltage on the GPU lines from the coils ?
2)
why is there no voltage to RAM from the 2 middle coils ?

3) why is there a beep to ground - is there a short somewhere in tha ram circuit ?
 

[Rasz]

probably junk bin candidate

[wraper]

3) why is there a beep to ground - is there a short somewhere in tha ram circuit ?

Low resistance likely is fine but not a complete short. "Beep" does not say anything about what it actually is.

[Sci666]

ok ...    but i dont understand why theres no voltage at the output side of the coils ....   so the mosfets didnt let the voltage through ?   because of ...   what can happen here ... maybe the PWM signal is missing ?   what happens if theres no PWM ? can i measure out the PWM signal here ?