350-400 Euro and no HDMI with HDCP output is way to much (I would even pay that much for a decoding card with HDMI and HDCP).
The GeForce 8400 from NVIDIA will be out soon and will cost much less that that and still feature PureVideo HD (a.k.a. PureVideo 2), it will have DVI with HDCP (but no HDMI port), all than and fan-less (heatsink only) perfect for HTPC computers. Then there is GeForce 8500 and GeForce 8600 from NVIDIA which all have HDCP and some can have HDMI (depends on the manufacturer), and even those are cheaper than 100 Euro. There is also AMD/ATI which features AVIVO hardware video acceleration, they even have card even features a built-in surround sound-chip.
Just read this article:
http://www.tomshardware.com/2007/06/..._purevideo_hd/
Then think about the direction of this hardware project again...
PS! All NVIDIA GeForce 8-series chips features the CUDA API support as well which means you could run other intensive processes on that GPU chip as well, (like post-processing filters, audio-decoding, etc.).
http://en.wikipedia.org/wiki/CUDA http://en.wikipedia.org/wiki/GPGPU