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820-3115 - Not turning on / Fan goes to full speed
- Thread starter mushr00m
- Start date
"PP5V_S3 = 0V
PP5V_S0 = 5.05"
That is not possible!
S0 voltage derives from S3.
Unless you have a broken trace to the point where you've checked 5V_S3.
Any history available?
Do you get CPU core voltage?
Tested in SMC bypass mode?
PP5V_S0 = 5.05"
That is not possible!
S0 voltage derives from S3.
Unless you have a broken trace to the point where you've checked 5V_S3.
Any history available?
Do you get CPU core voltage?
Tested in SMC bypass mode?
I don’t have a detailed history of this machine — it arrived a long time ago, and I remember working on it briefly before setting it aside. Unfortunately, I don’t recall exactly what was done.
At some point, I replaced the U7200, but it might have come from a donor board and could potentially be faulty — I’m not sure.
Just to clarify, PP5V_S3 is reading 5V as expected. (My mistake somehow yesterday)
Regarding the CPU core voltage, I’m not sure which specific line you’re referring to.
I haven’t tested the SMC bypass mode yet.
Any suggestions on the next steps?
At some point, I replaced the U7200, but it might have come from a donor board and could potentially be faulty — I’m not sure.
Just to clarify, PP5V_S3 is reading 5V as expected. (My mistake somehow yesterday)
Regarding the CPU core voltage, I’m not sure which specific line you’re referring to.
I haven’t tested the SMC bypass mode yet.
Any suggestions on the next steps?
Check voltage on all big coils.
Do not expect iGPU voltage yet.
CPU core stuck at 1.11V means the board doesn't really boot.
Check if PLT_RESET_L goes high.
Try known good BIOS.
CPU core stuck at 1.11V means the board doesn't really boot.
Check if PLT_RESET_L goes high.
Try known good BIOS.
By the way, I tried using a BIOS from another 820-3115 donor board, but I’m not sure if that BIOS was functional — unfortunately, it still didn’t work.
I do have a CH341 programmer, but I’m not experienced with BIOS flashing or cleaning the ME region. Do you think I should give that a try?
If so, could you guide me through the process?
I do have a CH341 programmer, but I’m not experienced with BIOS flashing or cleaning the ME region. Do you think I should give that a try?
If so, could you guide me through the process?
820-3115-B DTY3 Clean ME - OK.rar
drive.google.com
I used the CH341A to erase and reprogram the BIOS with your file, but unfortunately it still didn’t work.
It’s possible I made a mistake during the process, since this is my first time doing it.
Also, I had asked earlier about using a BIOS from an 820-2936 board—would that be compatible?
It’s possible I made a mistake during the process, since this is my first time doing it.
Also, I had asked earlier about using a BIOS from an 820-2936 board—would that be compatible?
Not compatible boards.
Check all SPI Bus Series Termination resistors and their traces/solders.
PCH/CPU may have corrosion underneath.
You can try to heat them with quality flux.
No need to melt the balls, just to burn eventually crap underneath.
Check all SPI Bus Series Termination resistors and their traces/solders.
PCH/CPU may have corrosion underneath.
You can try to heat them with quality flux.
No need to melt the balls, just to burn eventually crap underneath.
Try heating CPU too.
You can probably get second hand board for good price.
Think if is worth to invest time on this.
You can probably get second hand board for good price.
Think if is worth to invest time on this.
Do you get 1V05_S0_LDO and 1V5_S0_REG voltages?
Also check the voltages from page 22.
Also check the voltages from page 22.