I've always had a wierd tearing effect on my HTPC during busy scenes. The screen looks as though it refreshes the screen in about 3 stages. It's most prominent on panning shots. Like the screen is struggling to keep up. I put this down to the aging ATI AGP graphics card, and swapped the motherboard for a PCI Express one, and the card for an 2400XT. It's still there! I've also tried a couple of different MPEG2 decoders, and get the same result. The CPU is a 3.2GHz Pentium 4 HT (541). I've tried using HDMI and it's slightly better, but then the overall image is terrible, very rough, so for the time being I'm back at running the card at 1280x720 on my Pioneer 507XD. Any suggestions?