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Which card for maximum image playback speed?

Last response: in Graphics & Displays
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October 11, 2006 8:20:53 PM

I need to simultainiously display 4 digitized 640X480 video frames and 1 20 fps 1280X1024 image. Given a fixed CPU and Drive bandwidth who has the best bus to screen data transfer rate for displaying images to a 1600X1200 screen? Images are scaled and decompressed to fit. Assume PCI Express 16.
October 11, 2006 9:58:50 PM

I haven't ever seen benches of that, I doubt you'd see a difference with any two contemporary cards.

I would guess that's limited by the RAMDAC speed, and the new stuff is all pretty much on par.

Having said that, I'm pretty much making a guesstimate here. I could be totally off.
October 12, 2006 8:02:41 PM

I began my analysis by creating a worst case estimate of the amount of data being sent to the graphics card. First, let's equate 4 video frames to one 1280 X 1024 image. Then assuming 2 X 1280 X 1024 images with 4 byte pixel depth at 30 fps we get 1280 X 1024 X 4 X 2 X 30 = 314,572,800 bytes/second worst case. According to Intel (http://www.intel.com/design/chipsets/pciexpress.pdf) the PCI Express X16 bus is capable of handling 4 GB/s full duplex. Therefore, it doesn’t seem like the bottle neck is in the graphics card. The observation that the CPU is being maxed supports the conclusion that the bottle neck is earlier in the pipeline or possibly due to mishandling of the tasking of graphics card functions. Another, reference point is the fact that there are numerous applications that are being used to modify an incoming DVD data stream for display on high resolution LCDs up to 2560 x 1600 often with additional image processing.

This may all be hot air but this is where I am so far.
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