[SOLVED]820-3115, Single Beep after repairs

[dukefawks]

Check the PCH SMBUS on diode mode R5200/01. If one of the chips on that bus is fucked it will not recognize RAM. Backlight chip is a main suspect.

 

[SMMRepair]

Thanks, duke. Sure enough there's a short on pin 2 of R5200. I did have to replace the LED driver, but replaced with a new one. That area in general looks kind of like garbage, but I cleaned it up well. I'll check it over again.

 

[SMMRepair]

Ok I think this one has a fucked CPU. It literally just singed the fuck out of me. I didn't notice it before because I had a sink on it to test. Damn. Sorry about that Duke, you can close this one.

 

[dukefawks]

Unlikely, the CPU needs to work in order to produce a beep. Pull R9753/9757 and see if the short on SMBUS is gone.

 

[SMMRepair]

Hey Duke, I removed R9753/9757 and the short has gone, yes. Does this mean LP8550 is in fact the culprit? Or just that there's a short on one of the pins of LP8550?

 

[dukefawks]

No idea, pull it and replace.

 

[jadao]

I had similar if not the same issue in this post.
The post is for no chime board but initial issue looks same as yours. Please see conclusion.

https://www.rossmanngroup.com/boards..._vcore-present

 

[SMMRepair]

Damn, you guys are champs. I've replaced hundreds of LP8550s, but either goofed this one up or had a bad chip (I probably fucked up, can't blame the chips every time--chip came from a roll of 100 and all others were fine). In any event, this ugly ass board actually works now--thanks, you guys. Always nice to have a board come to life after 2-3 hours of work. I hope the CPU is OK--it literally singed me to the point of leaving a blister.

Duke, you can close this one up as solved. Board chimes and is breathing.