Acer Aspire 8530-754G64Mn Model MS2249 - black screen, not booting

[badhat]

Hello,
I've got my grandson's dead Acer Aspire 8530G-754G64Mn Laptop Model MS2249 on my 'dissecting table'. Pressing the power button gives back a few signs of life to it. The fan is spinning silently, the multimedia player's lights and volume-control touch slider appear to work but I can't hear a sound. An audio CD will spin for a little while but won't play. Screen and external monitor remain black. I removed battery, RAM and HDD, haven't found the RTC button cell yet. Both heat-piped processors, CPU and GPU card get about hand warm.

The only really working thing is the power button, it does both power-on and power-off.

What I did so far:
- plugged in a USB lamp which gets lit when the power is on

- plugged a POST diagnostic card into the free mini PCI express slot. It says "Signal Error: Check the PCU and Power Box". No CPU instruction steps.

- pulled the system HDD and extracted the latest logs and Local-Machine registry hive from it.

[HKEY_LOCAL_MACHINE\_REMOTE_SYSTEM\ControlSet001\Enum\PCI\VEN_1002&DEV_9612&SUBSYS_017D1025&REV_00\4&42db7a9&0&2808]
"DeviceDesc"="ATI Radeon HD 3200 Graphics        "
[HKEY_LOCAL_MACHINE\_REMOTE_SYSTEM\ControlSet001\Enum\PCI\VEN_1002&DEV_9480&SUBSYS_017D1025&REV_00\4&1970fb5f&0&0010]
"DeviceDesc"="ATI Mobility Radeon HD 4650  "

From what I read this 19" big laptop not only got two HDDs but also two ATI Radeon GPUs, an on-board HD3200 chip plus a Mobility HD3650 card. I haven't found the on-board GPU yet, will take out the keyboard tomorrow and have a deeper look inside the machine.

If I could only read the system logs, it seems they're not plain text files any more (as in the XP days). I'm using Linux, haven't cared much about recent Windows stuff ever since. Could anybody point me to reading Windows logs without Windows?

And of course, could anybody please give me some hints what to start with: BIOS or GPU(s)?

TIA,
Badhat

[badhat]

Re: Acer Aspire 8530-754G64Mn Model MS2249 - black screen, not booting

ps
sorry to bother you with that registry stuff. capacitors look ok.

[j_dabrowny]

Re: Acer Aspire 8530-754G64Mn Model MS2249 - black screen, not booting

There is a common problem with GPU in this model, just start with GPU....

[badhat]

Re: Acer Aspire 8530-754G64Mn Model MS2249 - black screen, not booting

There is a common problem with GPU in this model, just start with GPU....

Which one, 3200 on mainboard or 4650 on card?

[badhat]

SOLVED: Acer Aspire 8530-754G64Mn Model MS2249 - black screen, not booting

Happily solved!

BIOS, GPU, badcaps - what's your guess? :-)

[Scootie]

Re: Acer Aspire 8530-754G64Mn Model MS2249 - black screen, not booting

Well?

[badhat]

Re: Acer Aspire 8530-754G64Mn Model MS2249 - black screen, not booting

As you won't guess it anyway, here's the solution:

According to Acer's service guide I would have had to totally disassemble the whole thing in order to get to the lithium RTC battery (CMOS battery). So this button cell really was the last thing I'd like to check. But I found a shortcut.

I only had to remove 6 bottom screws to be able to pry open the left front corner of the case. I used a peace of wood to hold it open while replacing the button cell. The old cell had been discharged down to 0.7 volts (from 3.3 volts when new) and the laptop wouldn't boot. Replaced the cell and it's booting again.



Thanks for your patience :-)