Get over to HotHardware and read their review of 2 HDMI cards from ASUS, the EAX1600PRO and the EN7600GT.  Without spending huge amounts of money you can get HDMI compatibility and still bea ble to game.  These cards are not going to let you run at a huge resolution with every graphics effect at the max, but they really are better at sending high definition digital signals to large screens than hitting high fps in games.
“HotHardware evaluates the features, bundles, and performance of two HDMI-equipped cards from Asus, the EAX1600PRO/I/256M/A and the EN7600GT/HDTI/256M/A. As their names imply, these cards are powered by ATI’s Radeon X1600 Pro and NVIDIA’s GeForce 7600 GT GPUs. Head on over to the site and check them out…”

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