When run on an iMac G5 with a GeForce FX 5200 Ultra video card, the Aperture 1.5 Compatibility Checker shows the message
"Your graphics card is not supported."followed by
"Error: The installed graphics card does not meet the minimum system requirements by Aperture."
This happens on iMac G5 1.6 Ghz systems. Aperture 1.5 requires an iMac G5 running at 1.8 Ghz or faster, but the Compatibility Checker erroneously indicates that the graphics card is the reason the computer is unsupported.
This issue is resolved in Aperture 1.5.1.