This is, unfortunately, a known issue with the current Nvidia Vista drivers, and something that should be resolved soon. In the mean time there's not much you can do except use XP if it's something you can't tolerate.
John
Hey everyone,
Just posting something interesting that is happening. Everytime a website or DVD or anything uses windows media player in windows vista home premium, the video is painfully slow for about 2 or 3 seconds, while the audio rate is normal, then the video catches up and all is well. I have never had this problem in XP and have tried disabling and enabling different features of not only vista but windows media player. Any thoughts? Thanks
Brian
Dell E510
Intel Pent 4D 3.0Ghz
1 Gig Ram PC4300
2x 120Gig SATA HDD
PNY Nvidia 6600 256MB PCIe

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