dvd image is pixellated

[irv6744]

i am using an intel/hp/nvidia motherboard and my dvd playback on two different disks seems to slow down and become pixellated and then speed up and then repeat. in any case the image is randomly pixellated.
i installed the latest nvidia video drivers with no change. can't find screen in win winxp sp2 to make sure dvd is in dma mode. what else should i be checking.
thanks

[TechZ]

You need to see whether you have all your drivers installed, vga, motherboard especially. Also has this happenned before, or only on these 2 disks?
Which nVidia graphics card is this?
What application are you using?
Since you mentioned HP, is this a branded pc, if so which model.

[irv6744]

i have only tried it on the 2 dvd's that work ok on another computer. i have installed the nvidia drivers that cover all the motherboard components and have updated the video driver specifically. it is a geforce 3 driver on an hp board that i bought used and stuck in a case. everything else is fine. monitor resolution is 1280 x 1024 and maybe the onboard video cannot handle a dvd at that resolution. i don't have the computer in front of me but pretty sure it is an nforce2 chipset on an asus board. (not intel - i was wrong before). still looking for dma settings for the dvd. thanks

[irv6744]

i used a different version of powerdvd and now it works ok