I installed Ubuntu 13.04 with a USB Flash Disk since I did not have a DVD Disc. I chose Install alongside Windows 7 and followed the process. After it had the popup screen with Continue Testing and Restart Now, I clicked Restart Now and removed the Flash Drive. The PC continued to boot to Windows 7 even though it was supposed to pass Grub first. I already tried re-installing Grub on the ext4 partition but still no luck and it ended up making my Windows 7 Boot Manager unusable too.
System: Windows 7 Ultimate 64-bit 4GB of RAM AMD A4-5300 (with AMD Radeon 7480D IGP) 80 GB HDD Space (11.9 GB for Ubuntu) Gigabyte GA-F2A75M-HD2
Tried to install: Ubuntu 13.04 amd64