First, you need to settle down.
Second, you need to send a little bit of fear through your system, but only enough that you will work diligently. Now, you need to remember back to if you chose an option that LOCKES THE AGP/PCI BUS SPEEDS.
From the sounds of it, if you did not, you probably screwed you AGP port or card.
Now, to go back to the default settings of your computer, find the jumper on your motherboard to clear the cmos. It should be near the chip and the battery on your MB. Switch it so it connects the pin that is idle, and the middle pin. Run a couple of seconds of power thorugh your system. Switch it back and reboot.
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