Anywhere from none to many billions, depending on the computer.
Billions.
Integrated circuits (in many microprocessor integrated circuits) containing many billions of transistors each.
Like every other chip processors consist of millions of transistors.
Second generation
transistors
UNIVAC I
transistors
A computer can only understand two distinct types of data: on and off. A computer is just a collection of on/off switches (transistors). Anything that a computer can do is nothing more than a unique combination of some transistors turned on and some transistors turned off.
Of course. Transistors are the base of all computer processors. They are the successor to the vacuum tube.http://en.wikipedia.org/wiki/Transistor
758 Million transistors.
There are no valves in a modern computer. If by valves you mean vacuum tubes, the equivalent is a transistor. Modern CPUs have many transistors/gates on their dies. The SandyBridge i7, a near-top end general purpose computer COU can have 2.2 billon transistor elements on the CPU die. Of course there are many more transistors incorporated in the logic chips, controllers and video cards in a computer as well.
discrete transistors
second generation of computing