KenAF, I am no relation to STL. And yes I'm using the P4T-E. Per your request I tried the 150fsb, I should note all this is at DEFAULT core voltage, when using the dipswitches it disables changing the cpu voltage. Also worth noting is this is with the stock Intel retail heatsink.
With my 2 128 Samsung PC800's running at PC1200 I can get into XP no prob and run cpu and memory benchmarks but 3d Mark 2001 crashed shortly after starting. However with the rambus left at the 3X multiplier (PC800), the 150fsb at 2.4 gig is very stable and will run everything I've thrown at it so far. So my memory will handle PC1100 but that's about it, still not too shabby. I purchased these sticks Sept last year from Mushkin. I have 2 more 128 Samsung's that unbeknownst to me till yesterday are actually ECC sticks (we had mistakenly labeled them as non-ecc where I work). They cooperated fine together but didn't like overclocking above about 120fsb. I'll swap them tomorrow for 2 non ECC sticks and see if they perform any better. I want to be able to use all 4 sticks and still overclock of course though.