Your system could have onboard graphics GPU or a separate AGP video card in the AGP slot. Your docs should indicate ...if not...you'll probably have to go inside.
VAPCMD
I have a HP 8775C desktop. I have a AGP slot but can't figure out what it is. 2x? 4x? Without opening the case to look at the slot how do you tell. If you go to HP and look at the motherboard configuration, it just has a box that says AGP slot. I have looked in the pamphlet that came with it and can't figure it out.

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