acer predator 791g no power

[mosfetratus]

During use laptop simply shut off. also i was using throttlestop @ -150mV if this has anything to do with the problem.

when plugged in power supply goes to short protection, gives 0.50V.

Should i inject 19v into main power rail?

[mon2]

Re: acer predator 791g no power

Hi.

1) Never just inject voltage onto rails till more is known about the condition of your logic board.

2) Is your model also known as the ACER ASPIRE ?

3) PU4401 is the first mosfet that is mated with the DC adapter. We can start with that investigation.

Do you have the schematic & boardview files handy ?

4) Does your logic board look like the attached ?

[mosfetratus]

Re: acer predator 791g no power

Hi.

1) Never just inject voltage onto rails till more is known about the condition of your logic board.

2) Is your model also known as the ACER ASPIRE ?

3) PU4401 is the first mosfet that is mated with the DC adapter. We can start with that investigation.

Do you have the schematic & boardview files handy ?

4) Does your logic board look like the attached ?

acer predator g9-791g. Sadly i dont have schematics. p5ncn/p7ncn main board rev: 2.0

[SMDFlea]

Re: acer predator 791g no power

acer predator g9-791g. Sadly i dont have schematics. p5ncn/p7ncn main board rev: 2.0

Schematic,revision 1 but should be ok https://www.badcaps.net/forum/showthread.php?t=82221

Edit: and a boardview https://www.badcaps.net/forum/showpo...75&postcount=6

[mon2]

Re: acer predator 791g no power

Ok. Found the version 1.0 schematic in the database and perhaps v2.0 of the boardview file.

Does the attached look the same as yours ?

It is tied to the encrypted viewer that does not allow for saving so cannot share.

[mosfetratus]

Re: acer predator 791g no power

q8802 pin 5-8 is 5Ohmn, 1-3 77kohm, 4 is 100kohm. first mosfet

[mosfetratus]

Re: acer predator 791g no power

Schematic,revision 1 but should be ok https://www.badcaps.net/forum/showthread.php?t=82221

Edit: and a boardview https://www.badcaps.net/forum/showpo...75&postcount=6

strange that 17 and 15 inch models share identical boards. as its pretty accurate to mine

[mosfetratus]

Re: acer predator 791g no power

measured ohms on l8001 and i get 2.8, which is vcore. i think it's gg for the cpu

[mcplslg123]

Re: acer predator 791g no power

q8802 pin 5-8 is 5Ohmn, 1-3 77kohm, 4 is 100kohm. first mosfet

You have short in B+ or +19V rail. Remove R8800 and measure resistance on pin5-8 of Q8802 again. It should go up. Now measure resistance on R8800 both pads. The pad which is showing short needs voltage injection but max 1V. You can increase the Amp as much as you can. Something is likely to hot up. Find out.

[mcplslg123]

Re: acer predator 791g no power

measured ohms on l8001 and i get 2.8, which is vcore. i think it's gg for the cpu

That's fine. Dont mess unnecessarily here.

[mosfetratus]

Re: acer predator 791g no power

You have short in B+ or +19V rail. Remove R8800 and measure resistance on pin5-8 of Q8802 again. It should go up. Now measure resistance on R8800 both pads. The pad which is showing short needs voltage injection but max 1V. You can increase the Amp as much as you can. Something is likely to hot up. Find out.

pad 2, which is ac-bat-sys, is 5ohm. at this moment i need to fix my bench supply by replacing tl594c. Wait for update and thanks alot for the help . my shop only have tl594cd, is it ok to replace?

[piernov]

Re: acer predator 791g no power

Always check for shorted high-side MOSFET before injecting anything.

[mosfetratus]

Re: acer predator 791g no power

Always check for shorted high-side MOSFET before injecting anything.

i tested 8 pin mosfets that connects to ac bat sys. all look fine. problem is, that is not dead short.

[mosfetratus]

Re: acer predator 791g no power

found short. u8006 "advanced mosfet" :/ without injecting voltage, was too keen to findout.

is there a more available ic to cis631, hard to find any.

[mosfetratus]

Re: acer predator 791g no power

got mosfets but with G not T. Replace and computer works.

But i get artifacts. Screen is without artifacts when i uninstall intel drivers. Sheit.

https://imgur.com/a/9UWjBLp

[mon2]

Re: acer predator 791g no power

I think your screen resolution or refresh rate is too high for this display panel.

Test the idea with power up but run in SAFE mode -> then boot into Windows.

This will force the screen resolution to be VGA mode = 640x480 and see if you can read the graphics now with the display.

Once this is confirmed working, proceed to change the device driver settings for this display to be a lower resolution and lower refresh rate till you can max out the screen resolution (ie. 800x600, etc. and go up from there).

[mosfetratus]

Re: acer predator 791g no power

I think your screen resolution or refresh rate is too high for this display panel.

Test the idea with power up but run in SAFE mode -> then boot into Windows.

This will force the screen resolution to be VGA mode = 640x480 and see if you can read the graphics now with the display.

Once this is confirmed working, proceed to change the device driver settings for this display to be a lower resolution and lower refresh rate till you can max out the screen resolution (ie. 800x600, etc. and go up from there).

bios, safe-mode looks correct. Tried to test with each ram removed - same problem. I can't change refresh rate or make custom Hz. Only resolution, but still same problem with different resolution.

[mon2]

Re: acer predator 791g no power

bios, safe-mode looks correct.

Meaning that your display does not look like the shared 'overscan' image ?

You can read the text and view the 640*480 graphics in safe-mode ?

[mosfetratus]

Re: acer predator 791g no power

Meaning that your display does not look like the shared 'overscan' image ?

You can read the text and view the 640*480 graphics in safe-mode ?

Image is scaled OK in regular mode. Safe-mode works in 1080p rez.

[mosfetratus]

Re: acer predator 791g no power

furmark is like this :\

https://imgur.com/a/VoquX0n