3) do x86 chips use SOI technology to reduce Power leakage?
SOI or Silicon On Insulator is a fab tech that reduces cost and heat generation. So yes, thats true. If i remember AMD was the first to use such tech for their CPUs.
4) Does AMD have a equal to the PowerPC Dynamic Speed Controller (intel Speedstep)
Yes, they have. It's called Cool'n'Quiet (implimented in all AMD64 chips) and AMD PowerNow! implimented in AMD mobile CPUs.
5) What type of ZIF sockets are currently in use for x86 chips
There are various sockets for various CPU models. I'm not exactly into Intel CPUs and their sockets but AMD is using Socket A (Athlon4,AthlonXP), Socket 754 (Athlon 64), Socket 939 (Athlon 64), Socket 940 (Opteron), Socket AM2 (this is the latest one which is not yet available to buy).
It's also known that Pentium 4 are using ridiculously long pipelines in order to achieve higher frequencies. Thats why first P4's sucked big time compared to ultra fast Athlons in those days.