Looping on boot after first installation on Asus EEE PC 4G

[arrigo-pierotti]

Hi, I installed Lubuntu 15.10 on a little Asus EEE PC 4G (standard specs, changed only to 1 GB of RAM) and everything went fine but on first boot it gets stuck on this screen (see below) with kind of a blinking pattern (quick screen - black screen - long screen - black screen)
I tryed any key combination but nothing changes.

Someone knows why it does this and how to solve?
Thanks in advance
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