Hi! I'm back again... so I solved my previous issue but now it's back with a vengeance...
First, history... previous issue was dead motherboard, blinking power LED, no fan spin nor LED backlight, which was caused by a missing SLP_S5#. This was fixed when I replaced the RTC crystal.
Which brings us to the present. The screen started glitching every other 2 seconds. The screen corruption looks like the horizontal pixels/scan-lines are being shifted to different spots. This also happens on the BIOS setup. So I thought, "Okay, this might be my LCD since the thing has been showing signs of going out." I decided to test it out using an external display but I never got to that part because when I restarted from Windows, it decided to crap itself and not POST. Now the power LED just turns on, the fan spins, and the keyboard backlight comes up, then everything turns off all happens in about 3-5 seconds.
So I made the usual recovery procedure. Hard reset, BIOS reset, RAM re-seat/replacement, but nothing worked. So I decided to probe the board, I chased the entire Power On Sequence and everything, and I mean everything, is present and accounted for on the APU side. But the VGA side of things, the first thing on the sequence "PE_GPIO1(DGPU_PWR_EN)", is missing. So okay then, this might be a corrupt BIOS again, and fortunately I dumped all of the ROM chip in the board because of the previous fiasco. The backups are tested, all known good and working, so I removed the chip and flashed the backup and... nothing changed.
So okay then maybe there's a short somewhere on the PE_GPIO1 (DGPU_PWR_EN) line, so I checked with the multimeter and nothing is wrong in it. So as a test, I removed the jumper resistor RV403 and injected a voltage signal on the DGPU_PWR_EN side to see if the succeeding voltage rails will come up, and they did. Then I checked the resistance of PE_GPIO1 to ground and it's like 10kohms high.
I don't know what is needed for the APU to output PE_GPIO1(DGPU_PWR_EN), but from my test everything down the line are present.
One weird thing I noticed is that the control signals like "APU_RST# and APU_PWROK" the APU sends out reads low like 0.245V. Is this normal on this platform?
TLDR:
First, history... previous issue was dead motherboard, blinking power LED, no fan spin nor LED backlight, which was caused by a missing SLP_S5#. This was fixed when I replaced the RTC crystal.
Which brings us to the present. The screen started glitching every other 2 seconds. The screen corruption looks like the horizontal pixels/scan-lines are being shifted to different spots. This also happens on the BIOS setup. So I thought, "Okay, this might be my LCD since the thing has been showing signs of going out." I decided to test it out using an external display but I never got to that part because when I restarted from Windows, it decided to crap itself and not POST. Now the power LED just turns on, the fan spins, and the keyboard backlight comes up, then everything turns off all happens in about 3-5 seconds.
So I made the usual recovery procedure. Hard reset, BIOS reset, RAM re-seat/replacement, but nothing worked. So I decided to probe the board, I chased the entire Power On Sequence and everything, and I mean everything, is present and accounted for on the APU side. But the VGA side of things, the first thing on the sequence "PE_GPIO1(DGPU_PWR_EN)", is missing. So okay then, this might be a corrupt BIOS again, and fortunately I dumped all of the ROM chip in the board because of the previous fiasco. The backups are tested, all known good and working, so I removed the chip and flashed the backup and... nothing changed.
So okay then maybe there's a short somewhere on the PE_GPIO1 (DGPU_PWR_EN) line, so I checked with the multimeter and nothing is wrong in it. So as a test, I removed the jumper resistor RV403 and injected a voltage signal on the DGPU_PWR_EN side to see if the succeeding voltage rails will come up, and they did. Then I checked the resistance of PE_GPIO1 to ground and it's like 10kohms high.
I don't know what is needed for the APU to output PE_GPIO1(DGPU_PWR_EN), but from my test everything down the line are present.
One weird thing I noticed is that the control signals like "APU_RST# and APU_PWROK" the APU sends out reads low like 0.245V. Is this normal on this platform?
TLDR:
- Laptop No Post, Power LED, Fan Spins then off
- Checked entire power on sequence and required rails, all present
- Missing PE_GPIO1(DGPU_PWR_EN) signal
- APU control signals at 0.245V
- Reflashed BIOS with known working backup
Any ideas is greatly appriciated
Thanks!!! in advance
PS. Attached Schematics MOD EDIT: Link to schematics https://www.badcaps.net/forum/troubl...need-schematic