Hi Friends I am using 32bit Ubuntu 12.04 LTS ( Long Term Support ) on my laptop Lenovo B570E. My Lappy Configuration is Intel® Core™ i3-2350M CPU @ 2.30GHz × 4 , 4gb ram, 500gb HD. Few Days back when I was checking information about my processor in intel site .... I came to know that my Processor is 64 bit. Then I went to ubuntu site and checked the download page and it has 64 bit OS. Without any second thought I have downloaded that 64bit version and burned it onto CD and tried to install on my laptop as we can not upgrade an OS from 32 bit to 64 bit .. we have to do fresh installation. When I restarted my lappy and went to boot options and selected from DVD .. it gave an error message which says " Error: Prefix Not Set " and soon after this message some weird screen appears with some juggy vertical lines and some shit crap.... I had to shutdown the system forcibly. Some where I read that it might be the problem with the size of ISO image of the OS ... So I bought a DVD a...