The Pentium 166mhz is a old socket 7 a very early Pentium prossessor,The Pentium 4 is modern form factor,much faster and more prossessor cach than the old chips.
As a whole, the Pentium 4 has a higher maximum performance than a Pentium III. The Pentium III performs the same as or better than Pentium 4 at the same clock speed, but the Pentium 4 has a higher max clock speed (which the Pentium 4 was designed for).
No, you cannot.
They are no longer manufactured.
Yes, but it must be with one of the same type. EG, you can swap an Intel Pentium 3 1.5GHz with a Intel Pentium 3 2GHz, but not with an Intel Pentium 4 2GHz. Also, it must be the same socket type.
No, the Pentium 3 and Pentium 4 are not only samples of 2 completely different architectures, but also use a different socket so a change between the 2 on the same motherboard is impossible.
Series of processors / Generation of Pentium processors.
Intel Pentium processor
No. The Intel Pentium 4 line was produced for three sockets. The shortlived Socket 423, Socket 478, and LGA 775 (sometimes called Socket T).
Both processors are in the Pentium Dual Core family. The Pentium Dual Core E2200 is better than the other.
The Intel Pentium D, Core Duos (and Solos), Core 2 Duos (and Quads), Pentium Dual-Cores, and the Core i7.
That would require purchasing a new motherboard, processor, and power supply.
No. The Intel Core 2 Duo is much faster than the older Pentium 4.