Damn. Lost a dollar. Double or quits?
My new theory is that your sync pulse at 720 x 480 is too short. Have a look at powerstrip, you'll see the durations of the horizontal sync pulse, front porch, active area and back porch. This corresponds to one vertical line that makes up your image: The sync pulse says "start drawing the line now", there is a breif pause for the electron beam to get to the right point on the screen, then the active area when the image data for that line is sent, another pause, then the cycle starts again for the next line.
This happens 480 times per frame (at 640x480p) to produce one complete image, and this in turn happens sixty times a second (at 60 Hz).
I think that you need larger porch and sync settings - I saw the same issue on my 1031q, the image overlapped the raster and went a bit dim. The solution was to make the porches bigger and the active (image) area smaller, squeezing the image data into a shorter time window.
My powerstrip settings are shown below. This is for 848x480, which gives a 16:9 display. The porch settings are _much_ larger than the default powerstrip settings, I was surprised by how much I had to increase them. Be very careful when you make these changes, don't let the scan rate go over 36 kHz. I made my changes on a CRT monitor, checked that the timings were the same as for 640x480, then fired up the PJ.
Incidentally, I'm using 848x480 instead of 720x480 as this gives a 16:9 windows desktop. Purists will use a 720x480 desktop and set the aspect ratio of the display to 16:9 - great for watching DVDs, not so great for non-dvd (is. computer) use. This is all due to the non-square pixels of a DVD image.
As for composite sync - your graphics card has two outputs for sync pulses (horizontal and vertical), and three outputs for image signal intensity (red, green and blue). The 1031q has one sync input and three color inputs. The graphics card's two sync outputs are connected to the same input on the 1031q - in effect they are "composited" (combined) together. An alternative method of combining the horizontal and vertical sync data is for the graphics card to generate only one signal via one output. This is called "composite sync", and whilst it may well work with your computer monitor, it'll just confuse your 1031q. Thus in powerstrip, make sure that that the composite sync checkbox is unchecked.
Pete
PowerStrip timing parameters:
848x480=848,148,120,164,480,5,5,25,39552,278
Generic timing details for 848x480:
HFP=148 HSW=120 HBP=164 kHz=31 VFP=5 VSW=5 VBP=25 Hz=60
Linux modeline parameters:
"848x480" 39.552 848 996 1116 1280 480 485 490 515 -hsync -vsync
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