Well about a week ago I successfully installed Mac OS X Snow Leopard version 10.6.3 with Nawcom and a DVD containing Mac OS X. I decided not to dual boot, I was very excited to get Mac OS X. Everything worked out nicely until I noticed that my video card wasn't compatible. I did some research and decided I wanted Windows 7 back. I didn't have an actual installation disk for Windows 7 so I made a bootable Windows 7 USB. I started the Windows installation but as soon as I got to the 'Where do you want to install windows' part of the installation, it wouldn't let me install it onto any partitions. It kept giving me an error about how the partition was part GUID or something like that. I decided to go back into Mac OS and select the Master Boot Record option in the Partition Scheme (in Utility Disk). After I rebooted, my PC wouldn't load anything up. It'd just stay on the main boot screen, where I have the option to launch BIOS. When I hit ESC (to go to BIOS), it won't do anything... If I continue to hit ESC it'll start beeping. I'm not sure what I did. Please help as soon as possible.

I am new to working with partitions and other operating systems.

PC Specs:
HP Pavilion DV6
Intel Core i3 Processor
4 GB RAM

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