Did you measure or replace the cmos battery? Techs measure, the rest of us just pop in a new one. Not guaranteed to fix it but the clue is there that it could be the usual.
I have a dell inspiron which has 8 beeps and the lcd is not lighting.
I tryed the D+power button method and worked for twoo days. After I changed the lcd cable but nothing.
My friend has the same laptop so I asked hi's mother board and with the new motherboard is working.
Do I have a chance to repair the motherboard? or I need to buy a new one?