Pieter, I can't remember AquaMark 3 giving me a 1500+ pts difference between any runs at the same settings.
The average variation is around 300pts, and the max I've seen in my testing is about 800-900pts.

Once I get done with the P5Q3 Deluxe review I'll set up the system again and have it run AQ3 50 times with the QX9650 and 50 times with a E8600 at the same settings and tabulate the data.
TBH though, I don't think that the E8600 will get a higher score than the QX9650 at all.