I want to replace windows with Ubuntu, so I installed it on my hard drive from a USB stick and a CD, but every time I try to install it, and when it gets done installing, i reboot the computer but all i get is a black screen with a small line(the line that marks where you are going to type), like its trying to boot from something but it cant find it (I've tried to install it about 10 times). I have tried to leave the black screen up for 30min to see if it would boot, but nothing. I tried to leave the live Ubuntu up all night to see if it was still installing, but nothing, nothing but that black screen. I've also tried installing it onto my USB stick but when i boot from it it says "PRESS ANY KEY TO REBOOT." and if i press anything it just reboots. So can anyone help?
Computer info:
HP pavilion 520n
Intel(R) Celeron(TM) CPU 1300MHz
1.30 GHz, 512 MB of RAM