Nearly every modern processor has these or similar instructions, as they are necessary to implement multitasking.
If you're going to understand modern processors, you have to master these two concepts.
The call stack ranges from 4 to 32 entries in modern processors now.
The format of modern processors is almost always the two's complement binary number representation.
This is because a modern processor will usually try to keep blocks of code in its cache memory.
In addition, current (2010) modern processors use 64- or 128-bit logic.
Instead, another register was created to keep track of return locations on a separate stack area, like more modern processors.
Many modern processors use microcode for some of the commands.
A modern processor such as the Core i7 can crack it in a few seconds.
Clock multipliers on many modern processors are fixed - it is usually not possible to change them.