Ha! I'm using mine with a Rage Fury Pro 32MB card, too. You have to enable (well, you don't HAVE to, but it helps!) DMA for the DVD drive. In Windows 9x you do that in Device Manager. Control Panel->System->Devices->CD-ROM Drives->Pioneer..->Properties->Settings->put a check mark in DMA box. Reboot.
How long have you had the Rage card? Have you had any problems getting it working properly? Mine has been a bitch and a half, the OpenGL drivers don't always work perfectly even after trying every driver version, and finally I had to mix'n'match base drivers, OpenGL drivers, and D3D drivers (believe it or not, the D3D driver controls the quality of your DVD rendering on your monitor) from different driver releases to get it to work as good as it does now. But I will say the 2-D quality, DVD performance, and TV-out quality is excellent, and the video-in works fine, too.
Edit: I checked Pioneer's web site and there is no firmware update for this drive currently available - the drive was just recently introduced according to the info posted on their site.