Your card does not support pass-through. It would have to have 2x HDMI port on the back to do so (and then the hardware on the board to allow it).
If you are using the HDMI port on the 5670 as output, using a HDMI switcher would be your best bet. One cable from the GC to the switcher and one from the PS3 to the switcher, and then one cable from the switcher to the monitor.
Cloud (noun, singular): A dynamic arrangement of multiple potential single points of failure, with a user at one end and their data at the other.
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