Acer 7520g on and off

[dannyict]

Hi, just got this acer 7520g in and the thing just comes on with the light and turns back off...keeps doing this until I remove the battery. Bios does not come on.
Did 30 sec powerbutton, removed battery and put on good powersuply but still same. Is there any keycombination I can press to get into bios?
Removed memory, harddisk and dvd...nothing helped.
Is it the motherboard?

 

[meanderer]

one very far fetched method to find out would be swapping in a good motherboard. One last thing to try, boot it without a keyboard.

 

[MobileTechie]

It sounds like the loop is happening before it gets to the bios loading stage so not key combo will do it.

In which case it's almost certainly the motherboard since you've ruled out the only other possible causes.

 

[Cerberus LLC]

Bios

I just fixed a customers Acer last week from doing this. It turns out that her laptop was doing this because of running twin sticks of memory. It was a bios update that corrected this. It works fine now.

 

[meanderer]

I just fixed a customers Acer last week from doing this. It turns out that her laptop was doing this because of running twin sticks of memory. It was a bios update that corrected this. It works fine now.

hmm, is it right after a RAM upgrade?
OP did say he removed ram and doesn't help.

 

[KM@ Dave]

I know this sounds strange, but check the Wireless cards signal cable hasn't come loose and fallen onto the motherboard, thus causing it to 'short' out.

I know it sound very, very farfetched but I have seen this happen and seems similar, I'm not amazing at Laptop repair, to be honest I hate the damned things, but it's the last thing I noticed as it was lodged between two components on the motherboard prior to the customer fiddling with it.

Also, check that nothing has snapped off in things like the USB ports, HDMI and PCMCIA etc.

I hope this helps somehow.

 

[dannyict]

Thanks for all the help, tried all what was suggested here but still the same.
Conclusion must be the motherboard and replacing that is not cheap.