What is RAM?

Overview                                                    

Random Access Memory (RAM) provides space for your computer to read and write data to be accessed by the CPU (central processing unit). When people refer to a computer's memory, they usually mean its RAM.

If you add more RAM to your computer, you reduce the number of times your CPU must read data from your hard disk. This usually allows your computer to work considerably faster, as RAM is many times faster than a hard disk.

RAM is volatile, so data stored in RAM stays there only as long as your computer is running. As soon as you turn the computer off, the data stored in RAM disappears.

When you turn your computer on again, your computer's boot firmware (called BIOS on a PC) uses instructions stored semi-permanently in ROM chips to read your operating system and related files from the disk and load them back into RAM.

SDR, DDR, DDR2, and DDR3 RAM

Several types of RAM are used in modern computers. Before 2002, most computers used single data rate (SDR) RAM. Most computers made since then use either double data rate (DDR), DDR2, or DDR3 RAM. DDR2 is able to achieve faster transfer rates to prevent limitation of your CPU's performance, and DDR3 technology takes these advancements even further.

Note that these RAM technologies are not interchangeable. One type of RAM will not function if installed with another type, and physical differences in the RAM modules prevent them from even being inserted in the same computer.

Name Relation:

All of the friendly names have an industry name. Here are many of the common types in both the friendly and industry names:

DDR-200 : PC-1600
DDR-266 : PC-2100
DDR-300 : PC-2400
DDR-333 : PC-2700
DDR-400 : PC-3200

DDR2-400 : PC2-3200
DDR2-533 : PC2-4200
DDR2-667 : PC2-5300
DDR2-800 : PC2-6400
DDR2-1066 : PC2-8500

DDR3-800 : PC3-6400
DDR3-1066 : PC3-8500
DDR3-1333 : PC3-10600
DDR3-1600 : PC3-12800

概述

随机存取存储器（RAM）提供了空间主要为您的计算机读取和写入数据，以及对CPU（中央处理单元）进行访问。当人们提到到计算机的内存中，他们通常是指它的RAM。

如果你添加更多的RAM到您的计算机，这样就减少你的CPU必须从硬盘读取数据的次数。这通常让您的电脑工作速度要快，因为RAM比硬盘快很多倍。

RAM中的数据是容易丢失性的，它只储存你正在运行的程式或电脑插件。只要你关闭电脑，存储在RAM中的数据就会消失。

当你再次打开您的计算机上，计算机的的开机固件（BIOS在PC上）使用半永久性地存储在ROM芯片中的指令读你的操作系统和相关文件从磁盘，并将它们加载到RAM。

SDR, DDR, DDR2, 和 DDR3 RAM

现代计算机中使用几种类型的RAM。在2002年之前，大多数计算机使用单数据速率（SDR）RAM。大多数计算机使用从那时起，无论是双数据速率（DDR），DDR2，DDR3 RAM。 DDR2是能够实现更快的传输速率，以防止限制CPU的性能，DDR3技术，这些进步甚至是更进步。

请注意，这些RAM的技术是不能互换的。不同种类型的RAM将无法正常工作，如果与另一类型的一并安装，会在RAM模块产生物理差异，防止它们被插入在同一台计算机。

Ram 的名称:

RAM所有的称号，行业名称。这里有许多的例子和行业名称中的常见类型：

DDR-200 : PC-1600
DDR-266 : PC-2100
DDR-300 : PC-2400
DDR-333 : PC-2700
DDR-400 : PC-3200

DDR2-400 : PC2-3200
DDR2-533 : PC2-4200
DDR2-667 : PC2-5300
DDR2-800 : PC2-6400
DDR2-1066 : PC2-8500

DDR3-800 : PC3-6400
DDR3-1066 : PC3-8500
DDR3-1333 : PC3-10600
DDR3-1600 : PC3-12800