Benches were run with 512 MB on all systems, ATI radeon 9600 PRO, 64MB on Macs, 128MB on x86.
MP3: iTunes 4.01 / Magix MP3 maker 2003 diamond
MPEG-4: QT 6.3 / Windows media Encoder 9
P4 3.2 GHz = Dell Dimension 8300 Toronto
2x Xeon 3.06 GHz (with 1M L3) = Dell Precision 450
all other x86 self built by c't.
Additional Photoshop test with 2GB RAM:
2x 2GHz G5 : 261s
2x 3GHz Xeon : 260s
3.2GHz P4 : 316s
MacOS X was 6S80 for 2GHz and 6S74 for 1.8GHz.