Well, I just spent about 5 hours benchmarking PD 8,9, 10, and 11 with 4 different clips on 2 different machines with 4 nVidia video cards.
The whole data set is at
https://docs.google.com/spreadsheet/ccc?key=0AleSSO_7gwqedExrY01oNXVGYWJLdVBwY2ZnZmZkdnc
Make sure to look at the 4 different sheets at the bottom (benchmark1, benchmark2, benchmark3, benchmark4).
The conclusions are very sad.
Having multiple nVidia GPU actually significantly *reduces* the speed of rendering with all versions of PowerDirector.
If I physically pull one of the cards, or just disable the second card in Device manager, the speed is much improved.
Some example data, with benchmark3, the clip that takes the longest to encode.
From the Phenom x6 3.8 GHz box :
PD10 / single GPU, 560 Ti : 98 s
PD10 / dual GPU, 560 Ti + 8600 GT : 134s
PD11 / single GPU, 560 Ti : 145 s
PD11 / dual GPU, 560 Ti + 8600 GT : 182s
From the FX-8120 4.0 Ghz box :
PD10 / single GPU, 9800 GT : 254s
PD10 / dual GPU, 9800 GT : 543s
PD11 / single GPU, 9800 GT : 260s
PD11 / dual GPU, 9800 GT : 597s
There is something really, really wrong there.
While I didn't really expect mixing GPUs of different types was going to help much, I was extremely surprised to find that having two identical 9800 GT more than doubles the encoding time !
Definitely a case of less is more.
In most of my tests, PD11 came in significantly slower than PD10, but there are a few cases where it wins with benchmark1 and benchmark2 on the FX-8120 with the hardware encodes.
PD11 didn't let me do any software encodes, but I think that's because I'm using the trial version. For all the other versions of PD (8, 9, 10) I have registered licenses.
PD8 and PD9 can't coexist, but it's possible to have either PD8/PD10/PD11 or PD9/PD10/PD11.
Of the four versions overall, PD9 seems to be the fastest the majority of the time ...
MSI X99A Raider
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480 GB Patriot Ignite SSD (boot)
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6 x 1 TB Samsung 860 SSD (striped)
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