I bought my Dell in September 2012. The warranty period is already over, so it's fine that employees from Dell don't find my problem urgent. Anyway, this is my problem:
A few days ago, my laptop suddenly shut itself down while I was gaming. No warning, no sound, AC charger and battery plugged in so it can't be because of a power shortage. I rebooted and when I finished working on it, I put it in stand by. After an hour so I started it up again, but the laptop shut down immediately.
Now I started booting again but I noticed none of the lights on the laptop would light up. I only hear the CD drive and my HDD whirring. I managed to run the LCD test (D + power), and suddenly it rebooted normally.
After another shutdown that didn't work anymore the next time. I ran system diagnostics (Fn+power) and it didn't return any errors.
Any ideas would be greatly appreciated!