Ubuntu 13.04 on Acer x64 PC, only boots after starting recovery

Ubuntu 13.04 on Acer x64 PC, only boots after starting recovery

I have this strange problem with my Acer E1 421. First of all it's
important to say that I've upgraded this laptop's memory to 8gb RAM
instead of 2.
I decided to remove Windows 7 x64, and install Ubuntu, because I just hate
Windows. The problem is, the install went all fine, but when I try to boot
my laptop, this happens in order:
Boot laptop
Gets past BIOS Diagnostics
I see the purple Ubuntu thing
Screen goes black and stays that way until I press the Power off button
Boot laptop again
Gets past BIOS Diagnostics
I get an Ubuntu screen where I can choose Boot Normal/Recovery/...
I press Recovery
I don't do anything, simply click "Continue to Normal boot"
It works
Why do I always have to boot it up once, go through the whole recovery
without actually doing anything, to get it booted?
I'm using the GRUB bootloader.