VRM modify ICC_MAX to run high Current/TDP OEM processors

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RolloZ170

Well-Known Member
Apr 24, 2016
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View attachment 28331
The motherboard of 'impur NF5820M5' happens to have I2C0_ PWR three pin interface, but I am not sure if it is this interface that is used to modify VRM. Could you please answer the question
can you find the Ground pin in I2C0_PWR ?
if we know the pinout we can connect a MCP2221a device there and make a Bus scan.
 

rooloor

New Member
Mar 13, 2023
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install the MCP2221 Terminal and click Advanced settings.
set Address lenght to 7 bit and scan from 10h to 7Fh.
Can you send me the download link for MCP2221 Terminal;)
I've been searching for a long time and can't find MCP2221 Terminal.
 
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RolloZ170

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Apr 24, 2016
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Can you send me the download link for MCP2221 Terminal;)
MCP2221 I2C/SMBus Terminal (v2.0.1)
 

rooloor

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Mar 13, 2023
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Hi @ RolloZ170, here is the reading of scanning mcp2221a on the motherboard. Which address should I use? thank you
006.jpg
 

rooloor

New Member
Mar 13, 2023
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what happens ?
unable to unlock what ? used all addresses ? maybe there is another I2C header.
Okay, I'll give it a try.
By the way, do you know how to modify the BIOS? Start the motherboard with the modified BIOS, and the diagnostic card code will automatically shut down after displaying 92, which seems to be related to a watchdog!
 
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Stephan

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Apr 21, 2017
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Successfully modded a X11SPL-F rev 1.02 using Adafruit MCP2221a and BIOS 3.9 255W. CPU used is a slightly dead 8259CL and a slightly ECC challenged 32 GB Samsung DDR4 RDIMM from the trash bin.

Procedure was to just put the CPU in, turn on power so IPMI boots but not the system (CPU fan off). Run a scan using Microchip's terminal to see if SDA SCL GND are connected properly. GND is 0 Ohm to the USB connector housing shield, so easy to spot with beeping multimeter. Terminal should find around 10-20 addresses. Then run the patcher. Power-off power-on. Continue with BIOS...

Since the terminal is Windows only here is a script to attach and detach the MCP2221a device to a Windows VM on Linux KVM:
Bash:
#!/bin/bash

VM="YOUR_WINDOWS_VM_NAME_HERE"

USB1=$(virsh dumpxml $VM 2>/dev/null | tr -d '\n' | grep -Ei 'vendor id=.*04d8.*product id=.*0x00dd')
USB2="\
<hostdev mode='subsystem' type='usb' managed='no'>\
<source startupPolicy='optional'>\
<vendor id='0x04d8'/>\
<product id='0x00dd'/>\
</source>\
</hostdev>"

if [ -n "$USB1" ]; then
    echo $USB2 | virsh detach-device $VM /dev/stdin
else
    echo $USB2 | virsh attach-device $VM /dev/stdin
fi

exit 0
Edit: Power meter says 4.5W with only Aspeed BMC running, 52W Linux idle + empty (1 RAM Stick, 1 USB-Stick for booting Linux, 1 USB-Stick for Wifi).

Hottest chips at idle are the AST2500, a companion low-dropout RT9018B regulator (+5V ATX standby to what AST needs I presume), and a Realtek network chip also for the AST. Southbridge a hot mess, seems cooler than on Asrock. Other stuff is coils getting warm.

1.png2.png3.png
 
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jasonsansone

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Sep 15, 2020
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Just purchased an 8259CL to replace P-8136 on a X11SPL-F. Would everyone recommend a EVC2 or MCP2221a? Does anyone have they want to sell?
 

Stephan

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Apr 21, 2017
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Adafruit MCP2221a for 10 USD/EUR. Should not be in tight supply. You will need a 800..1500 rpm 120/140 fan with PWM e.g. sitting at the opposite edge of the board blowing at the VRM heatsink. Or some Supermicro OEM cooler which blows through CPU heatsink and right at it.
 

jasonsansone

Member
Sep 15, 2020
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Adafruit MCP2221a for 10 USD/EUR. Should not be in tight supply. You will need a 800..1500 rpm 120/140 fan with PWM e.g. sitting at the opposite edge of the board blowing at the VRM heatsink. Or some Supermicro OEM cooler which blows through CPU heatsink and right at it.
Thank you. I have the SNK-P0068APS4. Do you think that is sufficient when coupled with the chassis fans?
 

Stephan

Well-Known Member
Apr 21, 2017
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700
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Germany
This fan blows straight at the VRM, so ok. No idea if it can transport 210 watts away efficiently. Might get loud. Or be not enough even. Check CPU temp during CPU/RAM stress test. I run Memtest86 from Passmark and compile a linux kernel in RAM. The 8259CL needs 11min 5sec to compile my custom 6.2.16 kernel.
 
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