Wednesday, September 5, 2012

RAM: A small buying Guide

I recently bought a RAM for my laptop and really had troubles finding the right one. So, This is a short guide about RAM. How can you shop for RAM if you don’t even know what it is? Random Access Memory is a form of computer storage. It’s like your hard drive in your computer, but smaller and much, much faster. The part that makes it “random” is the fact that any data stored at any location can be accessed in constant time, meaning you don’t have to wait for the data to be found or for it to travel some distance to be read.

RAM is like, if your computer needs some piece of information it doesn’t waste time traveling to the address and getting the information, it can just get it. And no address in RAM is “closer” to its destination than another, for instance, the left side of the RAM chip isn’t read or accessed any faster than the right.

Also, your computer needs RAM to be able to even boot or do any task.

DDR (1,2, & 3) SDRAM – Double Data Rate Synchronous Dynamic Random Access Memory

These are the RAM's that one is going to look for when he is going to buy one for his/her desktop or laptop. Though laptop RAM's are smaller than desktops they also have one SO-DIMM type specifications.

DDR1

Standard Name  Memory      Clock Data Transfers/s         Module Name     Peak Transfer Rate
DDR-200  100 MHz 200 Million         PC-1600 1600 MB/s
DDR-266  133 MHz 266 Million         PC-2100 2100 MB/s
DDR-333  166 MHz 333 Million         PC-2700 2700 MB/s
DDR-400  200 MHz 400 Million         PC-3200 3200 MB/s

DDR2

Standard Name Memory Clock Data Transfer/s Module Name Peak Transfer Rate
DDR2-400 100 MHz 400 Million PC2-3200 3200 MB/s
DDR2-533 133 MHz 533 Million PC2-4200 4266 MB/s
PC2-4300
PC2-5300
DDR2-667 166 MHz 667 Million PC2-5400 5333 MB/s
PC2-6400
DDR2-800 200 MHz 800 Million PC2-8500 6400 MB/s
DDR2-1066 266 MHz 1066 Million PC2-8600 8533 MB/s

DDR3
Standard Name Memory Clock Data Transfers/s Module Name Peak Transfer Rate
DDR3-800 100 MHz 800 Million PC3-6400 6400 MB/s
DDR3-1066 133 MHz 1066 Million PC3-8500 8533 MB/s
DDR3-1333 166 MHz 667 Million PC3-10667 10667 MB/s
DDR3-1600 200 MHz 1600 Million PC3-12800 12800 MB/s

As you can see as the DDR level increases the Transfer rate increases. The better the DDR level the better the performance of the computer.
But Remember, your computer can support only one type of RAM. Before going to buy check what type of RAM does your system have and the same you can buy.

SO-DIMM (Laptop RAM)
SO-DIMM memory has the same specifications as regular DDR desktop memory except for the fact that SO-DIMM is smaller. Because of it’s smaller size it’s used in laptops and net-tops (like the Mac Mini). DDR1 and DDR2 SO-DIMM modules have 200 pins, whereas DDR3 SO-DIMM has 204.
NOTE: DDR1 and DDR2 SO-DIMM modules are not interchangeable, and the layout of the pins on the module prevent you from installing it into the wrong system.

Important Thing to know:
Windows XP (and other 32-bit operating systems) can only use 4GB’s of memory. This means 4GB’s of memory in the entire system. This includes your graphics card and any other peripherals that use even the slightest bit of memory.

This becomes a problem if you’re still hanging on to Windows XP but want a super-duper fast graphics card. Some graphics cards now have 1GB or 1.5 GB’s of video RAM, which means that will be taken out of the total 4GB’s that XP can address.

The answer: get a 64 bit operating system like Windows Vista x64 or Windows 7. Keep this in mind if you’re wanting lots of RAM but also wanting XP; there’s a tradeoff.