Solved! Asus A42JK powers on but no display or BIOS

[cowboy36289]

Hi guys,

I just took a leap, open up and upgraded my Asus A42JK from i5-520M to i7-840QM. Cleaned up and changed the fan and CMOS battery too. I put it back together, made sure everything is wired up properly as I took them out when disassembling.

I reinstalled by HDD and RAM and tried powering it on with the AC adapter. BUT, it powers on, power button and LED lights up, but the HDD LED shows none and my display is still off and doesn't show the logo, therefore I can't access the BIOS settings. The DVD drive spins up as normal upon power on and I can eject the tray by pressing the button. Pressing Caps doesn't show the LED. Fan runs slowly as it should, then ramps up after 10 secs blowing warm air, so I took it as a sign that the CPU swap is powered properly. It just gets stuck forever in that state until I hard shut it by holding down the power button. Needless to say, HDD didn't even spin up to boot.

What could be the possible issues? Is it:
1. CMOS battery
2. CPU swap not recognised by BIOS
3. One of the connectors not installed properly
4. Lid up/down detector got bogged during the disassembly process
5.???

Thanks for your time.

 

[rgd1101]

#2

 

[cowboy36289]

#2

I was starting to be inclined to think so too sadly...

 

[rgd1101]

Higher TDP, different processor core
http/www.notebookcheck.net/Intel-Core-i5-520M-Notebook-Processor.23749.0.html
http/www.notebookcheck.net/Intel-Core-i7-840QM-Notebook-Processor.31149.0.html

 

[cowboy36289]

Do you think it'd be wise to perform a BIOS hack by updating the microcode? I found out that the current CPUID 106E5 (for the Nehalem processors) in the BIOS is ver.3. I found another laptop with a ver4 (dating from late-May '10) microcode for this CPUID but I'm not sure if it supports the 840QM (released Jun '10). Couldn't find a more updated version that I can access and patch to the BIOS though.

 

[rgd1101]

wise? if it doesn't work, you brick your laptop.