Deskmini A300 - SOC + CPU hardware voltage mod

[Shaun2029]

Deskmini-A300-SOC-and-CPU-Voltage-Hardware-Modification
Deskmini A300 SOC Voltage modded to 1100mV - VCORE Max 1388mV

GitHub - shaun2029/Deskmini-A300-SOC-and-CPU-Voltage-Hardware-Modification: Deskmini A300 SOC Voltage modded to 1100mV - VCORE Max 1388mV

Deskmini A300 SOC Voltage modded to 1100mV - VCORE Max 1388mV - shaun2029/Deskmini-A300-SOC-and-CPU-Voltage-Hardware-Modification

github.com

I was unable to get my Ryzen 4600G stable with PBO turned on. I tried to increase the SOC voltage using different BIOS versions but nothing worked.

After modifying the SOC voltage to around 1.100V, there were still stability issues. I managed to solve this with a +112mV VCORE offset, by adding another resistor modification.

My Deskmini A300 is using BIOS P3.60S with a Ryzen 4600G an PBO is set to enabled.


The Deskmini a300 uses a DS3667BB-02 Dual-Output PWM Controller.
Data sheet: Dual-Output PWM Controller - DS3667BB-02.pdf


SOC Voltage
Linking 5V via 150K resistor to RT3667BB pin 24 (OFSA) about 112mV Offset to CPU VSOC. For 4600G, SOC increased from 1000mv 1100mV
NOTE: In pictures this resistor is linked with the white wires.

82K resistor, offset ~206mV
120K resistor, offset ~150mV
150K resistor, offset ~112mV
240K resistor, offset ~75mV
360K resistor, offset ~50mV


CPU VCore Voltage Offset
Linking 5V via 17.5K resistor to RT3667BB pin 23 (OFS) ~160mV Offset to CPU VCORE. For 4650G, VCORE max increased to 1388mV (PBO ON)
NOTE: In pictures these resistors are linked with the pink (red) wires.

17.5K resistor (22Kin parallel with a 150K and a 220K resistor), offset ~160mV

22K resistor in parallel with a 150K resistor, offset ~90mV - unstable


Notes:
Although I have been as diligent as possible, I accept no responsibility for the information in the document, or the damage that it could lead to.

This is very risky, you can destroy your Deskmini A300 CPU RAM drives etc.

The components are very very small, only do this if you are very experienced soldering tiny components and have the correct equipment (soldering iorn with a very small diameter tip), and a lot of time.

Do not heat the entire resistor, it will detach from the board and it will be game over. Only touch one end of the component with the soldering iron, and only for a fraction of a second. I used leaded solder and an iron tip temperature of 380 degrees celsius.

Disconnect the power and all peripherals during the procedure.

Use wire with a very small diameter.

 

[Shaun2029]

Correction - Core Performance Boost is enabled, not PBO.

 

[Shaun2029]

I now realize that this post belongs in the MODS forum section.

 

[msystems]

Hello, really excellent work.

Since you seem to be really competent at this, would you have any idea how to modify the vDimm to raise it above 1.35v (ideally 1.5-1.65v). My understanding is this involves adding a (variable) resistor on the voltage sense path for the pwm voltage controller that controls vDimm. This would unlock up to another 15% FPS in games. When I examined the board for clues, I didn't find any other obvious pwm voltage controller besides the RT3667BB. I still have no idea how vDimm is controlled on the board.

 

[Shaun2029]

Thank you.

Have you looked at the bottom of the board? There seems to be a power stage there. This is from images I have found on the internet. My Deskmini is installed and I do not want to take it apart just yet. It feels like I have taken it apart around a hundred times

If you can get me some high resolution images of the area surrounding the RAM slots, top of the board and underneath. Pictures that I can use to read the chip numbers. Perhaps I can spot something. Use a macro camera setting if you can.

What RAM speed are you going for?

 

[Shaun2029]

I have posted images here with the possible RAM power stages.

Album — Postimages

postimg.cc

I have not looked but DDR4 probably requires a few different voltages, a DDR 4 pinout may help find the correct power sage to modify.
The trick is to find the correct one, and what IC is controlling it as you have pointed out.

The IC should be a lot simpler and smaller than the RT3667BB.

 

[msystems]

Ok. Yes there are some tiny bits back in that area. 8 or 16 pinouts that only have a few characters printed on their surface and I don't get anything from Google.

As for the dimm pinout:

https://media-www.micron.com/-/media/client/global/documents/products/data-sheet/modules/sodimm/ddr4/asf18c1gx72hz.pdf?rev=d419808db2164eb9ac5e060ad05e9ca9

Page 4, "VDD" pins = power supply, (1.2v JEDEC default)

 

[Shaun2029]

Ok. Yes there are some tiny bits back in that area. 8 or 16 pinouts that only have a few characters printed on their surface and I don't get anything from Google.

As for the dimm pinout:

https://media-www.micron.com/-/media/client/global/documents/products/data-sheet/modules/sodimm/ddr4/asf18c1gx72hz.pdf?rev=d419808db2164eb9ac5e060ad05e9ca9

Page 4, "VDD" pins = power supply, (1.2v JEDEC default)

So are you suggesting follow the vdd traces in reverse right?

Yes, you can use a multi-meter set to resistance, or continuity to test your guesses.

 

[msystems]

Ah ok I thought that's what you were getting at but wasn't sure as I've not tried something like this before. Nice idea

 

[Shaun2029]

Yes, you can use a multi-meter set to resistance, or continuity to test your

Be very careful, this is risky and can lead to tears.
Remove both the RAM sticks before proceeding.

The VDD of the SODIMM RAM slot will probably connect to the capacitor of the power stage.
In the pictures above, these are the larger yellow/orange components near the grey components marked 2R2 and R47.

Google: SMD capacitor, specifically

Multilayer Ceramic Capacitor​

The 2R2 and R47 components are inductors. These inductors are connected to the power transistors (MOSFETs or FETs) . The transistors are in a tiny IC with hardly any writing. The transistor IC is connected to a PWM signal source of some description.

In the case of the SOC and CPU, the PWM signal is provided by the DS3667BB-02.

You are looking for something smaller connected to the transistor package.

 

[Shaun2029]

Make sure the Deskmini is unplugged
Good luck!