Thomas Halahan wrote:
I don't understand why I can't get my K6-2 400MHz, and Rage IIC greaphics card to give good playback. In the DVD howto I see that you need io ctrl in the Kernel. Could it be that I do't have this feature enabled? Is it really that critical. I guess I want to know what is the likely weakest link in my setup as I really know nothing about hardware.I just recently started playing with DVD on my Linux box, and it was horribly, unwatchably jumpy. Then early one morning as I was about half an hour before waking up, still kindda in that dream state, I remembered hdparm.Tom
At my work I had seen jumpy DVD playback on Windows machines, and turning on DMA access helped. So I ran the command:
sudo hdparm -c1 -d1 -X34 /dev/dvd and that made a tremendous difference.The -c1 turns on 32-bit addressing, and the -d1 turns on DMA access, and the -X34 was recommended by the man pages when using -d1. /dev/dvd is a symlink to /dev/cdrom which is a symlink to /dev/hdc which is where my dvd/cd drive sits.
HTH Kent
Video RAM is nearly irrelevant. Anything with 2MB can do 1024x768/16-bit which is what you want for DVD. For film-source DVDs you want 72Hz or 96Hz refresh so you need a RAMDAC of 82MHz or 110MHz respectively. The other consideration for video cards is that it really must have an implementation of Xvideo for XFree86, hardware color space conversion, hardware scaling, and it must have enough video memory bandwidth to convert/scale at 1024x768/16. Briefly: you need at least a Matrox Millenium (c. 1995). Regarding the rest of the system, any 350MHz+ CPU with a vector math unit will work. Pentium II/III/IV, Celeron, Duron, K6, Athlon, G4 should be fine. Once you get to zero dropped frames, there isn't a lot of point in piling more hardware on. -jwb