Have recently installed Ubuntu 12.04.2 LTS by USB on my newly built custom pc and I have run into a problem during installation with the error saying "No root file system is defined." My pc speculations: AMD Phenom x4 955 Black Edition ASRock 960GM/U3S3 FX Micro ATX AM3+ Motherboard Mushkin Redline 8GB (2x4GB) DDR3-1866 Memory Seagate Barracuda…