Acer Predator X34 No Power

[m_12adel]

Hello
I have Acer Predator x34 that power led is blue which means power on
but no display, no led, Altera daughterboard no led
Led 19v exist, 5v, 3.3v, 2.5v, 1.7v, 1.2v are exist
power supply is 19v with not stable 007 to .011 A
Board number is 715G8996-MOD-000-006K
Any suggestion or board viewer or datasheet?

[BowlOfSomething]

Hi!

I have a similar problem. Did you manage to solve the issue?

If not; I ordered replacement capacitors to replace the existing ones to see if that's the problem. I noticed that the right 35V 150uF capacitor has no voltage on the positive lead and traced it to the QA6VA chip on the back side. Most of the pins seem to have 0V, but 19V is present and so is ground.
If you happen to know what the QA6VA chip is I would greatly appreciate it, as well as any info you might have.

[SMDFlea]

Hi!

I have a similar problem. Did you manage to solve the issue?

If not; I ordered replacement capacitors to replace the existing ones to see if that's the problem. I noticed that the right 35V 150uF capacitor has no voltage on the positive lead and traced it to the QA6VA chip on the back side. Most of the pins seem to have 0V, but 19V is present and so is ground.
If you happen to know what the QA6VA chip is I would greatly appreciate it, as well as any info you might have.

Post a good clear picture of the QA6VA chip so that we can see the marking on top of it

[BowlOfSomething]

I took this image a couple of days ago, but it's as clear as I can get it with my phone's macro lens. There might be some cotton swab residue on the chip but I think the markings are clear enough.
I have asked on electonics stackexchange and another user guessed it might be a Silergy chip, but so far I wasn't able to determine which one it might be. The capacitor is connected through the 2R20 resistor and an inductor on the other side of the board so I'm guessing it's a power IC.

I'm not certain this chip is faulty, it might be missing some input but without a datasheet it's hard to determine.

[BowlOfSomething]

As per my friends' instructions I replaced all capacitors on the mainboard and it changed nothing. I then turned to check for blown fuses and resistors. To my surprise, I spotted 2 0.2Ohm resistors which were reading 1MOhm across. They're labelled R811 and R858 on the board and seem to be connected to one of these big mosfets or diodes (I'll check again today).

I desoldered the two offending resistors and found that one reads as 4MOhm and the other as OL. Do you think something else might be damaged on the board or could I just replace the resistors and test?

[BowlOfSomething]

Welp I only found a pack of 500 resistors for a reasonable price and reasonable delivery time, so I'll have a few to sacrifice if they failed.

[BowlOfSomething]

Yeah that did nothing but I should have expected that to be fair... They only connected the negative pin of the lower capacitor to ground.