i installed ubuntu alongside windows 8.1 over an usb drive on my lap top. At first i had problems with boot selection menu and i fixed it with EasyBCD now i have another problem i boot up my lap top and then it takes me to chose windows 8.1 or ubuntu i press ubuntu and it takes me to grub menu now i chose there ubuntu 12.04 and it starts to boot for few secs then my screen goes black and nothing happens few secs later i hear like short error noise and still nothin happens. Can someone help me solve this problem?