Acer V3-571 No Display and Shutdown With Ram

[ronelex]

good day, I have this unit dead set and missing 5v and 3v alw after solved, it turns on but missing supply on +VGFX core supply and shut off after 2 seconds if ram is inserted. the boardcode is LA-7912P and an UMA version.
I have already done reflash both ec and bios and replace the bios chips and already checked the power sequence

[kropotkin]

Re: Acer V3-571 No Display and Shutdown With Ram

+VGFX appears when much and more things have successfully passed tests on this mobo. The conclusion could be drawn from your problem description is: 1) MB starts to POST and sees the difference b/w RAM installed or not. If you can share LPC bus state - would be nice. Try another CPU/RAM? Is memory voltage rails available/stable with RAM installed?

[ktmmotocross]

Re: Acer V3-571 No Display and Shutdown With Ram

+VGFX appears when much and more things have successfully passed tests on this mobo. The conclusion could be drawn from your problem description is: 1) MB starts to POST and sees the difference b/w RAM installed or not. If you can share LPC bus state - would be nice. Try another CPU/RAM? Is memory voltage rails available/stable with RAM installed?

dont ever use LPC bus. How can i use it to diagnose fault?

[kiraro]

Re: Acer V3-571 No Display and Shutdown With Ram

I have the same issu with Lenovo laptop and finally i changed KBC and it's work fine with ram . try to change it

[ronelex]

Re: Acer V3-571 No Display and Shutdown With Ram

sorry for the late reply, thanks for the tips, I will use it if I encounter again this issue, the owner is in a hurry of the unit I return it because I hold it for 1 week. Quarantined hit our place and I cant go now on my shop, thanks for the response

[ronelex]

Re: Acer V3-571 No Display and Shutdown With Ram

I have the same issu with Lenovo laptop and finally i changed KBC and it's work fine with ram . try to change it

I also have Lenovo laptop here 320 when in bios it is ok, but if it enters the OS int shutdown