I have a Dell E6430 laptop with 4GB of RAM. I replaced it with 2x4GB modules. After that the laptop turns on, checks the DVD drive, doesn't beep, doesn't show anything on the screen (no access to BIOS). Sometimes it can work like that for an hour, sometimes it turns off by itself.
I decided to return to the original RAM modules. Got the same behaviour. I double checked all the modules, both new and old - they all work on my other laptop.
But that's not the end of the story. After googling this issue I disconnected the CMOS battery, waited a bit, plugged it in and succeeded. The laptop finally turned on with the original RAM and showed the Dell logo. And then I decided to do the same trick with the new modules. It failed, they just don't work, so I reinstalled the old ones, repeated the procedure with CMOS battery and... it didn't work out this time. I have the same problem as before and can't get through it.
Are there magicians who know what's going on here and how to fix it? I wasted several hours on this mumbo jumbo, and I have no idea how to bring it back to life.
Additional information: after turning off the indicators start signalling. Precisely, the HDD is on and the battery is blinking.