Well, it looks like there’s something odd about the eBay-bought GeForce graphics card on my G5. I’ve asked a couple of people to test my VVVVGradients composition on their machines, and everything has worked fine for them. It works fine on my MacBook Pro, and has now been tested on a G5 iMac running 10.5, on which it also works fine. On my G5, however, this happens…
..the right side of the image disappears, whenever I turn on a particular option.
It should look like this:

