Here ya go, I was just re-reading it right now:
The Yamaha RX-V663 is capable of upconverting analog signals to its HDMI output, so we put it through our video testing suite. We connected the Panasonic DMP-BD35 via component video to the RX-V663, with the DMP-BD35 set to 480i output. The RX-V663 was set to output at 480p (which is the highest resolution for upconverted signals) over its HDMI output, connected to the Panasonic TH-65VX100U.
As soon as we had the RX-V663 upconverting analog signals, we could see significant image instability, as even the setup menus of the DMP-BD35 looked pretty shaky. We loaded up Silicon Optix's HQV test suite in DVD, and the RX-V663 performed very poorly on the initial resolution test, compressing both vertical and horizontal resolution, which caused flickering and shakiness all over the image. The next two video-based tests were just as bad, as we observed a rotating white line full of jaggies, and the same thing on three pivoting lines. It also failed the 2:3 pull-down test, as we could see signal moire in the grandstands as the racecar drove by. AV receivers often struggle with video performance tests, but the RX-V663 was definitely below average.
The RX-V663 seemed to be reducing resolution more than normal, so we also took a quick look at our Avia test disc on DVD. We fired up its main resolution test pattern and the issue became clearer (or fuzzier, depending on how you look at it). The RX-V663 reduced horizontal resolution to about 400 lines, but vertical resolution was reduced all the way to somewhere between 300 and 350 lines of resolution. That's severe enough that even nonvideophiles will probably notice something isn't right.
Moving on from test patterns, we fired up the opening scene to Star Trek: Insurrection. As you'd expect from the test patterns, it looked pretty rough as it failed to kick into 2:3 pull-down processing mode, and the reduced resolution was readily apparent. Next up was the difficult introduction scene from Seabiscuit. Again, the RX-V663 struggled, with jaggies filling nearly the entire screen during the pans of black and white photographs. It's hard to recommend this receiver for upconverting analog video signals.
On the upside, it's worth pointing out that the RX-V663 also does not scale incoming HDMI video signals, and instead passes them perfectly through to the display. This means that if you only intend to use the HDMI video inputs on the RX-V663, you can ignore the previous comments on video performance, as they only apply to analog signals.