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<blockquote data-quote="Tech Geek" data-source="post: 61391" data-attributes="member: 18181">HDTV on a low end card and you are having problems.&nbsp; Where have I heard this before?&nbsp; (see the ATSC related thread)The AGP 8X slot only handles about 2.1 GB/sec so if you want HDTV resolutions I'm guessing that's one potential problem due to the way playback is handled by the mode MediaPortal uses for video (VMR9).&nbsp; It seems to need a lot of buss bandwidth.However, the requirement&nbsp; itself is related to just memory bandwidth.&nbsp; The card has to deinterlace/scale the image and that's where the problem lies.&nbsp; Video in 19xx by 1080 24 bit color requires quit a bit of bandwidth just to display let alone do any processing on it.&nbsp; Width x height x color depth adds up in a hurry in HDTV plus deinterlacing or scaling.&nbsp; If you use standard DVD resolution you shouldn't have problems on a low end card.&nbsp; But when you double the resolution vertically and horizontally you increase the bandwidth usage by at least 4 times.&nbsp; Then add deinterlacing and scaling without hardware support on many low end cards and your CPU is trying to squeeze that back and forth over a 2.1 GB/sec buss.&nbsp; If you want HDTV resolution you're going to need a pretty serious graphics card.&nbsp; Notice, my PCIx X1300 will beat a 9550 but I still had difficulties with HDTV resolution and VMR9.&nbsp; My X1300 had just under 10GB/sec memory bandwidth at the standard clock speed but I had problems with live HDTV from MediaPortal.</blockquote>

[QUOTE="Tech Geek, post: 61391, member: 18181"] HDTV on a low end card and you are having problems. Where have I heard this before? (see the ATSC related thread) The AGP 8X slot only handles about 2.1 GB/sec so if you want HDTV resolutions I'm guessing that's one potential problem due to the way playback is handled by the mode MediaPortal uses for video (VMR9). It seems to need a lot of buss bandwidth. However, the requirement itself is related to just memory bandwidth. The card has to deinterlace/scale the image and that's where the problem lies. Video in 19xx by 1080 24 bit color requires quit a bit of bandwidth just to display let alone do any processing on it. Width x height x color depth adds up in a hurry in HDTV plus deinterlacing or scaling. If you use standard DVD resolution you shouldn't have problems on a low end card. But when you double the resolution vertically and horizontally you increase the bandwidth usage by at least 4 times. Then add deinterlacing and scaling without hardware support on many low end cards and your CPU is trying to squeeze that back and forth over a 2.1 GB/sec buss. If you want HDTV resolution you're going to need a pretty serious graphics card. Notice, my PCIx X1300 will beat a 9550 but I still had difficulties with HDTV resolution and VMR9. My X1300 had just under 10GB/sec memory bandwidth at the standard clock speed but I had problems with live HDTV from MediaPortal. [/QUOTE]

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