Laptop to HD plasma display connection. Our office has a Panasonic HD plasma TV (model TH-42PX64)

Question

Our office has a Panasonic HD plasma TV (model TH-42PX64) with 2 HDMI jacks and we would like to use it as an accessory display for presentations from the laptop. It does not have a RGB or PC jack. The manual indicated that a PC to DVI cable would connect them however there is not a DVI jack on this TV. Purchased this cable online (recommended by Radio Shack Store locally) and it required a DVI to HDMI adaptor (purchased at another Radio Shack store) and it did not adapt to DVI male due to no plave for two pins on top and bottom of flat pin on male end. Called 1 800 Radio Shack and they recommended a PC to DVI adaptor and a DVI to HDMI cable. Purchased online and it connects correctly, however the signal does not transfer from a regular desktop output to the TV nor from the laptop to the TV and it seems to interfer with the display switching of the laptop accessory display toggle. Any ideas are appreciated!