Modify RAM 2Go to 4Go for Lenovo S20-30

[unplugged82]

Hi Room!

I have a Lenovo S20-30 with 2GB RAM. I soldered a RAM on the motherboard (same reference as the original one) and unfortunately, the motherboard only detects 2GB.

Should I modify the BIOS so that the system displays and detects the 4GB of RAM?

Thanks in advance

[JaroTech]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

What are the part numbers of the old and new memory?

[unplugged82]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

Thank's for your reply,

Here is a picture of the reference

D9PXV MICRON BGA

[JaroTech]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

On page 9 of the schematics, you need to configure the resistors for the new Micron memory, removing some and adding other resistors for the SDRAM configuration.

[unplugged82]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

I didn't see it!

I will do it tomorrow and come back here for the result

Thanks for the info

[unplugged82]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

Here is a screenshot of the area for GPIO
When I move the R286 to R284 it does not work. The PC starts but no image.
Could you help me if there is another combination?

[JaroTech]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

I think you should take R294 out and put it at R293.

[unplugged82]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

...still the same

[JaroTech]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

If you put the resistors back as they were before changing the memories. What happens afterwards?

[unplugged82]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

If i put the resistors back, it work's fine but just with 2Go of RAM

[unplugged82]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

https://fr.aliexpress.com/item/40000...yAdapt=glo2fra

I found on Aliexpress a motherboard with 4Go of RAM (Samsung RAM chip)

[JaroTech]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

You have 8 circuits for memory, U5 U6 U8 U9 U72 U73 U74 U75. Originally which circuits were present and which were added.

[unplugged82]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

U5 U6 U8 and U9 was the original
U72 U73 U74 and U75 was added

Thanks for your reply

[jasko_jacker]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

Check r416 , a photo effect or a problem ?

[unplugged82]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

The resistor is ok, 0.245K ohm
No short anywhere detected. it works fine when the RAM is in single chanel

I used this RAM to pick up the chips

[jasko_jacker]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

at this point one of the new chips may be damaged. personally even if the work is so much I would try to replace the working chips (old 2g), one at a time, with the new ones and see if it displays (with 2g cdefault conf)

[unplugged82]

Re: Modify RAM 2Go to 4Go for Lenovo S20-30

That's exactly what I thought and we'll see what happens