My problem was solved.
First of all I wanted to remove fglrx
$ sudo apt-get --purge remove fglrx*
Then, I tried to install the latest ati driver.
(I downloaded driver file from AMD wibsite http://support.amd.com/us/gpudownload/Pages/index.aspx
$ sudo sh ./Download/amd-driver-installer-catalyst-12.10-x86.x86_64.run --buildpkg Ubuntu/quantal
$ sudo aticonfig --initial -f
It was failed.
After that, I'v installed fglrx again.
$ sudo apt-get install fglrx
I could see AMD Catalyst Control Center on Preferences.
I turned on TV.
PS. I don't know how it was working. However, my concern is that installing the proper driver is important.