|I had exactly the same symptoms on my 1520. Whilst the advice given suggested 'replacing' the Mem Modules, I carried out the following procedures & brought my 1520 back to full operation without ANY expense.|
Follow preparatory procedures, then:-
get access to both Mem Cards & mark them Top & Bottom.
Test 1520 & Mem modules by trying to boot of 1 only.
Remove Top - retry. Does it Boot? or note LEDs.
Fit T remove B - retry. Does it Boot? or note LEDs.
Fit B in T - retry. Does it Boot?
Fit T in B - retry. Does it Boot?
If the above does not identify a definate bad Mem module, you need to remove sub assembly modules from the MB & reseat them one at a time; HDD; Wlan; DVD etc. You can then repeat the above tests. My 1520 Booted after reseating Wlan & HDD. Good luck.