Here a comparison for testing/educational only purpose about some "Real World" micro-benchmark on iDeneb v1.4 OSX86 and the upcoming Ubuntu Linux 9.04
Hardware
CPU: Intel Core Duo E8400 @ 3.0Ghz
MB: Asus P5Q
Graphic Card: Radeon 4850 @ 1920x1200
OSX86 Customizations
BIOS firmware 2002 Juzzi
ATL1e