Lenovo Legion 15ach6h ic chip fried

[Lenovochris]

Lenovo Legion 15ach6h ic chip
Can anyone help with id for it please
Pu6601 location on board

[mon2]

Silergy SY8288RAC AWSxyz IC

https://www.aliexpress.com/w/wholesa...tesla.search.0

[Lenovochris]

Silergy SY8288RAC AWSxyz IC

https://www.aliexpress.com/w/wholesa...tesla.search.0

Thanks for that, It's just a case of soldering on yes?

[mon2]

Correct. Flux and remove first. Clean the pads - be patient and watch lots of YT videos. Not wanting to burn the board nor remove the small PCB pads that keep this QFN package onboard. Practice on donor boards to get a feel. You will need hot air tools for sure or work with a good local cell phone tech.

Once the regulator is removed, test the resistance to ground on the output pins to confirm there is no shorted part onboard. That is, this part did burn out for a reason and it may be due to an excessive load.

[Lenovochris]

Correct. Flux and remove first. Clean the pads - be patient and watch lots of YT videos. Not wanting to burn the board nor remove the small PCB pads that keep this QFN package onboard. Practice on donor boards to get a feel. You will need hot air tools for sure or work with a good local cell phone tech.

Once the regulator is removed, test the resistance to ground on the output pins to confirm there is no shorted part onboard. That is, this part did burn out for a reason and it may be due to an excessive load.

Thank you for that, i have a hot work gun and flux and have done bios chips etc and caps before, but really appreciate the advice. As we are all here to learn. I'll be on contact again when I have removed the old one , Hopefully will go smoothly, 400 degrees c for removal or less, thanks

[mon2]

Measure the resistance to ground of PL6601 (without power to the board). Is it with a very low resistance? Trying to understand why this regulator fried.

[Lenovochris]

Measure the resistance to ground of PL6601 (without power to the board). Is it with a very low resistance? Trying to understand why this regulator fried.

Thanks for your help. Unfortunately upon chip removal there is evidence the chip exploding has caused irreparable damage to the board surface.

So I have ordered a second hand board with. Same part number etc,
This has a fault of its own but I don't want to but new just yet,
It goes no display but displayed on hdmi previously apparently if swap my old bios chips from old board to new, will this retain the s/n etc from the original laptop.
Thanks

[m1ch43lzm]

If you're getting picture via HDMI, the issue is most likely not the BIOS
For the S/N, etc, on AMD laptops you can swap the main BIOS with no issue, on Intel you have to clean ME region, or edit the BIOS from the working board with the S/N from the dead board
No need to swap anything which "looks like a BIOS", only swap UB3 (or UB2), W74M12JWSSIQ or W74M25JWZEIQ whichever is present

Some boards use a MUX for switching the display between the iGPU and dGPU, others connect the LCD to iGPU, and wire the HDMI port to the discrete GPU, check the schematics
If your board is NM-D562 the schematics are here https://www.badcaps.net/forum/troubl...-and-boardview
it has a MUX, UV12 PS8461E, replace it with the one from the dead board, then check if you have picture on the Internal LCD

[Lenovochris]

If you're getting picture via HDMI, the issue is most likely not the BIOS
For the S/N, etc, on AMD laptops you can swap the main BIOS with no issue, on Intel you have to clean ME region, or edit the BIOS from the working board with the S/N from the dead board
No need to swap anything which "looks like a BIOS", only swap UB3 (or UB2), W74M12JWSSIQ or W74M25JWZEIQ whichever is present

Some boards use a MUX for switching the display between the iGPU and dGPU, others connect the LCD to iGPU, and wire the HDMI port to the discrete GPU, check the schematics
If your board is NM-D562 the schematics are here https://www.badcaps.net/forum/troubl...-and-boardview
it has a MUX, UV12 PS8461E, replace it with the one from the dead board, then check if you have picture on the Internal LCD

IHi
Thanks for the response,
I've attached the description of the boards faults from the previous no owner.

It is indeed an Nm-d562 rev 3.0 Both are Ryzen 7 5800h motherboard with 3070s

[m1ch43lzm]

The power off issue after X seconds may be a similar issue as this one
https://www.badcaps.net/forum/troubl...ter-34-seconds
Also check if it responds to pressing Caps Lock on the keyboard while it's on (caps lock LED should toggle), if it does then the no display issue could be a faulty mux

[Lenovochris]

Ok thanks, when I get home tonight I will check and update, sorry for.my ignorance what is an mux.
Thanks

[m1ch43lzm]

Mux is abbreviation of multiplexer
https://en.m.wikipedia.org/wiki/Multiplexer
Think of it as a controlled switch, you have the display outputs from the AMD graphics built in the CPU, and the NVIDIA GPU, it's used to switch between those to the internal LCD
When the BIOS is set to "Integrated" it tells the mux to route the display output from the AMD iGPU to the LCD, and when running a game it will switch the LCD to the NVIDIA GPU

When it was set to "discrete", it's set to route the display output from the NVIDIA GPU to the LCD (the AMD iGPU is disabled), that's why the seller claims it showed display from HDMI only, as the HDMI port is wired directly to the NVIDIA GPU

That's why I suspect a faulty mux, check page 45 of the schematics

[Lenovochris]

Ah ok
Thank you.for that I will look through and see if I can understand it thank you..

[Lenovochris]

If you're getting picture via HDMI, the issue is most likely not the BIOS
For the S/N, etc, on AMD laptops you can swap the main BIOS with no issue, on Intel you have to clean ME region, or edit the BIOS from the working board with the S/N from the dead board
No need to swap anything which "looks like a BIOS", only swap UB3 (or UB2), W74M12JWSSIQ or W74M25JWZEIQ whichever is present

Some boards use a MUX for switching the display between the iGPU and dGPU, others connect the LCD to iGPU, and wire the HDMI port to the discrete GPU, check the schematics
If your board is NM-D562 the schematics are here https://www.badcaps.net/forum/troubl...-and-boardview
it has a MUX, UV12 PS8461E, replace it with the one from the dead board, then check if you have picture on the Internal LCD

Ok
So I installed the used motherboard to test.
Fans come on on start up like normal and go off
Keyboard lights on, caps lock doesn't toggle light on
Fans kick in for a period of time then the whole machine shuts down,
I don't have a great understanding of schematics, I did have look and all it did was confuse me.
I can't seem to find uv12 on the board or the temp ic chip for the apparent shut down issue
Am I looking in the wrong place,
I've attached pictures of the old board could you circle the area I should be looking in. Sorry to be a pain.
Thanks for all your help.

[m1ch43lzm]

The boardview should help https://www.badcaps.net/forum/troubl...10#post3178010
Open with FlexBV Free https://pldaniels.com/flexbv5/
UV12

[Lenovochris]

Ah perfect thank you,
This will be my first job tonight then I will let you know how I've got on, thank you so much

[Lenovochris]

The boardview should help https://www.badcaps.net/forum/troubl...10#post3178010
Open with FlexBV Free https://pldaniels.com/flexbv5/
UV12

I think this is the one, any advice on lining up when resoldering to make sure all pins line up?

[m1ch43lzm]

Here's some videos how to solder QFN, you need a microscope to inspect the pins for shorts
https://www.youtube.com/watch?v=ozD5NELBpP0
https://www.youtube.com/watch?v=kmX_oLPy08o
www.youtube.com/watch?v=uLEyxEF6_MU
https://www.youtube.com/shorts/9vicndfU5sA

Practice on dead boards first

[Lenovochris]

Here's some videos how to solder QFN, you need a microscope to inspect the pins for shorts
https://www.youtube.com/watch?v=ozD5NELBpP0
https://www.youtube.com/watch?v=kmX_oLPy08o
www.youtube.com/watch?v=uLEyxEF6_MU
https://www.youtube.com/shorts/9vicndfU5sA

Practice on dead boards first

Thanks for the links very helpful, will give it a go tonight and see how I get on, will let you.lnow the results.
Thanks