.:*Chache-RAM og Rom*:.

Read-Only Memory:

ROM is \"built-in\" computer memory containing data that normally can only be read, not written to. ROM contains the programming that allows your computer to be \"booted up\" or regenerated each time you turn it on. Unlike a computer\'s random access memory (RAM), the data in ROM is not lost when the computer power is turned off. The ROM is sustained by a small long-life battery in your computer.
If you ever do the hardware setup procedure with your computer, you effectively will be writing to ROM.

Cache Memory :

Cache memory is random access memory (random access memory) that a computer microprocessor can access more quickly than it can access regular RAM. As the microprocessor processes data, it looks first in the cache memory and if it finds the data there (from a previous reading of data), it does not have to do the more time-consuming reading of data from larger memory.
Cache memory is sometimes described in levels of closeness and accessability to the microprocessor. A L1 and L2 cache is on the same chip as the microprocessor. (For example, the PowerPC 601 processor has a 32 kilobytes level-1 cache built into its chip.) L1 and L2 is usually a separate static RAM (static random access memory) chip. The main RAM is usually a dynamic RAM (dynamic random access memory) chip. SRAM does not have to be electromagnetically refreshed as DRAM does, and is therefore more expensive. A popular SRAM (or cache memory) size is 1048 kilobytes (1 megabyte). Typical DRAM sizes are 4 megabyte to 32 megabytes.

In addition to cache memory, one can think of RAM itself as a cache of memory for hard disk storage since all of RAM\'s contents come from the hard disk initially when you turn your computer on and load the operating system (you are loading it into RAM) and later as you start new applications and access new data. RAM can also contain a special area called a disk cache that contains the data most recently read in from the hard disk.

Hvis du har et bundkort hvor der er en slot tæt på processoren, så er det der du kan indsætte flere cache ram.
Ideen med cache ram er, at den skal prøve at forudse hvad de næste data, som processoren får brug for er. Den tager så disse data fra de almindelige RAM, som er meget langsommere end cache rammene, og sender dem til cpu\'en. Dette gør arbejdshastigheden hurtigere. slotten til cacherammen er placeret så tæt på processoren, da jo kortere afstand...jo højere hastighed.

Håber det har uddybet lidt.

takker for points :)

www.fotx.net/kimrosgaard