Many people have found difficulty getting their Sigma Designs Hollywood+ DVD decoder card working in WinXP (The card is also branded Creative Dxr3).
Here's how I managed to get it working.

1) The Pass through cable must go to the primary video card. If you are using multiple monitors, the AGP must be set as primary in the BIOS and in Windows.

2) Download the latest software (I used 2.3) from www.sigmadesigns.com and install in the default location (C:\REALmagic),

3) The screen should be set at 16bit colours. Resolution doesn't seem to matter.

There are lots of problems with this card and neither Sigma nor Creative show any signs of producing XP certified drivers. This card doesn't seem to run under certain motherboards - for more information checkout news://news.sigmadesigns.com