PCI GPU

[CanadaRox]

I was thinking of using my Atom rig that I was planning to use as a router as a HTPC, but I don't think the 1.6GHz Atom 330 and 945G onboard is capable of 1080p playback. The problem is, the motherboard only has a single PCI expansion slot, which leaves my choices for GPU rather limited. I was hoping for something that could do HD decoding as well as HDMI with both video and audio, but I don't know if something like that exists. Hopefully someone has a suggestion as the best I seem to be able to find is an HD2400Pro, which can't do HDMI audio (and some of the Newegg.ca reviews say it can't even do HD decoding).