820-2936 burned q7100

Micheal Harris

New member
No signs of water damage at all.

q7100 burned and ruined the traces under it, so after scraping away the damage and making sure nothing was shorted, i soldered a new one upside-down stuck to L7100, and the fan spins!, until the new q7100 gets hot enough to melt the solder on it within a few seconds, ruining q7100 and it gets stuck open, and did the same thing with another.

the rail it is switching has a 0.003 drop to ground, witch i figured was normal since it is low voltage cpu rail, I'm thinking the cpu is bad, and will simply kill any q7100 i put there.

looking for any input, because it sounds like a rabbit hole to me.
 

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dukefawks

Administrator
U7100 is bad for sure and 0.003 to GND is too low. Remove U7100 and Q7100 and check resistance again. I'm afraid your CPU is also fried. U7100 and Q7100 are certainly dead again replace only as a pair.
 

Micheal Harris

New member
forgot to mention, i did replace them as a pair, and the resistance does not change when i remove them both

i figured the cpu was bad, just wanted some kind of confirmation before i waste more time on it, thanks.
 
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