Shortcut Math For Job

3.5. Internal Cache Memory

While working the CPU stores its program and data in the RAM. There are 2 main types of RAM – static and dynamic.
i) Static RAM or SRAM: Faster and 10-20 times more expensive than DRAM.
ii) Dynamic RAM or DRAM: Slower and 10-20 times less expensive than SRAM.

Click here to download the book. 

To save money, the PC uses a lot of DRAM, but it decreases the PC’s speed. To get some speed, small amount of SRAM is used in to the CPU.

This SRAM is called the cache memory. The size of the cache memory is much smaller than the main memory.

The often-used data is stored in this cache memory. Thus the CPU need not access the relatively slow DRAM and the overall speed increases.

There are 2 types of cache memory – internal and external. A PC can have any one or both or none of these two.

i) Internal cache memory: This cache memory is built in to the CPU. It is also called level-1 or L1 cache. Size of the internal cache memory is smaller than the external cache memory.

ii) External cache memory: This cache memory is built on the motherboard. It is also called level-2 or L2 cache.

The Pentium processors normally have 16K internal L1 cache and 256-512K external L2 cache. The Pentium-Pro has all the 2 level cache built in to the processor.

3.6. MMX Technology

For multimedia operations (video, audio etc.) MMX processors can work faster and with improved quality of color and sound. The MMX versions of Intel processors use 57 special purpose instructions. These instructions can work in parallel. These instructions are used to speed up the core algorithms, which are often used for multimedia operations.