
576 THE x86 MICROPROCESSORS
17.7 | Memory – SIMM and DIMM
e theoretical aspect of semiconductor memory was discussed in Chapter 12. Here, we will
see how these theoretical aspects matter, in the world of personal computers. e amount of
physical memory that can be used for a Pentium Pro chip is 2
36
bytes, where 36 is the number
of address lines it possesses. is comes to 64 GB of physical memory space, which is a very big
number. Having this much of RAM is prohibitively expensive, and takes a number of DDR
chips and a number of sockets to put them in. e maximum capacity of current DDRs is only
2/4 GB. In practice, the RAM that most ...