Re: HD Stuttering on 720p HDTV but not 1080P Monitor
Did you try setting the TV as a primary monitor? Or even use it as a single monitor by unplugging the Dell? I know hardware acceleration sometimes goes a bit wonky on a secondary monitor. The same goes with hardware overlays, where if you start playback on the primary monitor and move the window over to the secondary, there could be some slight synchronization issues. For example, your Dell could be using a 60.25hz timing while your TV uses a 59.75hz timing; both would be reported at 60hz while still not being in sync.
As for the hardware acceleration, that is a bit odd; I tried turning hardware acceleration on and off in PowerDVD and CPU usage went from 25-30% to 50-55%. I'm admittedly using a C2D at 2.66ghz (same gfx card), so it's not quite comparable. Does PowerDVD use all 4 cores on your system? If so, your CPU usage may be normal, but if it only uses 2 cores it's a bit on the low side, especially with hardware acceleration off. Then again, it may all be moot and irrelevant to the issue.
You can check if it's using hardware assist by setting the CLEV setting in PowerDVD (which is only available with acceleration off) to split screen. If you see a split image, hardware assist is off.
A third thing I'd like to ask is what resolution is your TV set at, and what is it's native resolution? TVs tend to treat signals a bit differently depending on resolution, and if it's (say) a 1360x768 panel and you're feeding it a 720p signal then it may be treating as a television broadcast or DVD player and using overscan and all sorts of post-processing 'enhancements' which may be further affecting playback. I assume you can pick some other resolutions on your TV than you've been using (say, 1280x768 or even 800x600); you might want to try playback at those resolutions just to see if you still get the stutters. Ideally, you'd want your TV to treat the signal as a computer signal rather than a television/DVD player signal.
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