Nice bit of effort you've been putting in there mr Lobber, that sure made some interesting reading.

Scary how similar the curve of my run looks like OPB's superrun, iirc i was using the CDT tweak at that time, although i doubt it was done 100% right.

The lenght of the fist slope that you suspect memtimings are responsable for are interesting even though i have my reservations on that thought.

Memtimings can't be compared when there are so many variables such as memspeed and chipset imo.
It's the combination of the memorytiming at that certain speed and how the chipset reacts to that, P35 could possibly react different than X38, which makes one chipset much more senstive to a certain memory (sub)timing than the other.

I for one, found out the hard way that 400FSB on a 965 chipset is enough to get sub 13 minutes 32M at 3.6GHz as long as the memspeed is very high.

Try the same on a P35 chipset and you won't be able to do that, P35 needs more FSB to get things done.

Pretty much the same applies for memorytimings i reckon.

Still, your scientific approach with those graphs visualizes what's actually happening which is great to see.

KTE, i agree with you on the inconsistency of the superpi output results, especially in 1M runs, one day gettin sub 14 seconds at 3.6GHz is a snap, the other day i'm really struggeling to get there.

As a final word on the CDT tweak, the 1.8Gb rar file has got to be on the root of your drive, so no maps or submaps involved, this might impact the effect of this tweak.