Guide to buying RAM (Random Access Memory)

When it comes to improving the performance of your computer, increasing the amount of RAM is the easiest and possibly most effective way of boosting speed and handling power. All computers ship with a specified amount of RAM, and most mother boards have extra capacity to install additional RAM which can be done without a trip to the service centre providing you purchase the correct RAM for your computer and you follow a few simple rules. You can use Myshopping.com.au to source the correct RAM for your machine and compare prices.

RAM is an acronym for Random Access Memory. During computation, you computer uses the RAM to hold the program code and process instructions that you give your software. When you turn your computer off, RAM loses the data that was used during the computing session. This is called volatile and when you restart your computer the data from the operating system and the programs you start is once again loaded into the computer?s RAM. (Although modern RAM still retains small portions of data as either dynamic DRAM or static SDRAM.)

RAM functions as the fuel tank of the computer?s central processor unit (CPU) allowing portions to be partitioned to provide a fast access hard disk (although volatile) which is particularly useful when using programs that require large amounts of processing power such as media manipulation software. As you process more data in a session, RAM fills up and your processor continually needs to go to the hard disk to retrieve data with which it overlays the old data in RAM. This slows the ?crunch? speed of the computer.

RAM enables the data that it stores to be accessed in a random order rather than sequentially as in hard drives and permanent media and therefore continuously updated. This allows it to be both written to and read from continuously as the computer processes data. The RAM inside the computer is sometimes called the primary storage. It is usually a circuit board (commonly called a memory card) containing a bank of integrated circuits that plug into slots on the computer?s motherboard. Modern motherboards have multiple slots for memory cards. The more RAM you have, the longer it takes to ?fill up? with data during a computing session. Increasing the RAM has the effect of speeding up processing because there is less need for the processor to continually call upon the hard drive for data.

RAM memory cards come in various sizes physical depending on the requirements of your motherboard. The main measurement for the card sizes is the number of pins, or connections, it has that seat it in its base. Some are dual sided; others are single sided. RAM is also a relatively small memory. New computers now commonly come with single chipsets of 256 Megabytes, 512 MB, 1, 2 and 4 Gigabytes of RAM. It?s not uncommon in professional machines used for multimedia work to have configurations up to 16 GB of RAM. You can search Myshopping.com.au for RAM based on the size you require. The other key specification is the speed given in MHz and usually associated with chip speed rating.

Dell, Compaq, Toshiba, Gateway, HP and some other computers require specific memory part numbers to meet the specifications of their processors. You don?t need to buy memory from the company that made your computer, as this can be more expensive, but it is important that you choose the part number or model that is specified. It?s important to check on the specifications required by your motherboard. One way to do this is to look at the card that is already installed in the computer, noting its type and model number. You can then search for similar model numbers and compare memory size and price on Myshopping.com.au. Another way is to search the name and specifications of the maker of the motherboard and choose RAM specified by them. Usually it is specified as the type of RAM required (a PC number) and the number of pins available in the card slots.

Modern desktop PCs use either Intel or AMD processors, and some have dual memory processors, such as the Intel Core Duo. Knowing what processor is the first step. It?s also important that any memory you buy matches your memory BUSS speed. Common speeds are PC66, PC100, PC133, PC2100, PC2700, PC2-3200, PC2-4200, PC2-5300, PC2-6400, and PC2-8000.

Common speeds for RDRAM are PC600, PC700, PC800, and PC1066. The newest types of RDRAM are not listed as a PC number. Speeds are listed as RIMM1600, RIMM2100, RIMM3200, RIMM4200, RIMM6400, and RIMM8500. These new type or RDRAM chips will not fit in place old style RDRAM.

While the following list is not exhaustive, it covers the main SDRAM memory cards in use in modern computers. Older computers and some printers may use smaller capacity cards than those listed below. However the same principles apply; once you have determined the type of memory card in your computer, search Myshopping.com.au for cards with similar specifications.

DDR2, 240 Pin memory is used in the newest and fastest Computers. These cards measure 133mm x 45mm and have one notch along the pin surface approximately in the middle of the card. 120 pins are on the front of the card and 120 pins are on the back. This is a leading-edge generation of memory with improved architecture that allows it to transmit data very fast. They are available in DDR2 PC2-3200 SDRAM, DDR2 PC2-4200 SDRAM, DDR2 PC2-5300 SDRAM, PC2-6400 SDRAM and PC2-8000. For systems that make use of dual channel memory mode, you must have two memory boards that are exactly the same or the dual channel portion will not work. Get two memory chips with the same part number if you want dual channel.

DDR 184 Pin memory is used in newer desktop computers. These cards measure approximately 136mm x 25mm and have one notch located at about one third of the length of the pin surface. These are dual sided cards with 92 pins on each side available in PC2100 DDR SDRAM, PC2700 DDR SDRAM, and PC3200 DDR SDRAM. For systems that make use of dual channel memory mode, you must have two memory boards that are exactly the same or the dual channel portion will not work. Get two memory chips with the same part number if you want dual channel.

SDRAM 168 Pin memory is used in older desktop computers commonly found in Pentium (1,2,3,4) and Athelon systems. These cards measure approximately 136mm x 25mm and have two notches along the pin surface: one approximately a quarter of the distance along, the other in approximately the middle. These are double sided with 84 pins on each side and are available in EDO, 66MHz SDRAM, PC100 SDRAM, and PC133 SDRAM. When upgrading, be sure to match the memory technology that is already in your system.

Rambus RDRAM RIMM 184-pin memory is a general purpose high-performance memory module. It is used in a broad range of applications and particularly applicable where high bandwidth and low latency are required. These cards measure approximately 133mm x 32mm and are available in high speed 1066, 800, 711 and 600 MHz configurations.

SODIMM 200 pin DDR memory is used in newer Laptop computers and iMac Intel core duo machines. These cards measure about 67mm x 25mm and are available in sizes up to 2 GB. They are double sided with 100 pins on the front and 100 on the back and a small notch appears in the row of pins about a quarter of the length from the left side. This is a leading-edge generation of memory with an improved architecture that allows it to transmit data very fast and is available in DDR2 PC2100 SDRAM, DDR2 PC2700 SDRAM, DDR2 PC3200 SDRAM, PC2-SO3200 SDRAM, PC2-SO4200 SDRAM, and PC2-5300 SDRAM configurations.

SODIMM 144 pin memory is also primarily used in laptop and small profile computers, like the original tray-loading iMac computer. The card measures approximately 67mm x 25mm with 72 pins on the front and 72 pins on the back and has a notch in the pin edge offset from the middle. They are available in FPM, EDO, PC66, PC100 and PC133 configurations.

DIMM 100 pin memory is used in some printers and may be used in older laptops. The cards measure approximately 88mm x 31mm and have two notches in the pin edge. They are available up to 128 MB.

If you have one of the newest and fastest desktop computers (Intel dual core, AMD processors) your computer will likely use a DDR2 240 pin card. A slightly older machine (Intel Pentium processor greater than 2.0 Mhz, Mac G5) will likely use a DDR 184 pin card. Older machines (Pentium 4, Athlon, Mac G3, G4) will likely use a SDRAM 168 pin card.

For the latest model laptops iMacs and Mac PowerBook you will likely use a 200 pin DDR2 SODIMM or DDR SODIMM card. Older Pentium laptops and Mac PowerBooks (G4, G3) will likely use 144 pin DDR SODIMM.

If you are unsure what you machine uses, check the details that are printed on the memory card that is currently installed and search Myshopping.com.au for similar models.

Once you have purchased the correct RAM to upgrade you computer, installation is a simple matter and can be easily performed by following a few simple instructions.

Unplug the computer
Before you do anything, shut down your computer and turn off the mains power and unplug everything attached to it.

Inspect the case
Some cases have a thumb screw closure; some have a couple of screws and some, like the Apple G3/G4 series have a simple latch and a swing-down lid. If you are in doubt, look at your user manual. Put the computer on a table or bench top in a place where you can work at it easily.

Ground Yourself
Static electricity is Enemy Number One of integrated circuits. Because these circuits operate at very low voltages and because they include capacitors that store electrical charges, any static electricity that may discharge from your fingers while you are working with the memory card has the potential to cause irreparable damage. Therefore, before you touch anything inside the computer, touch some bare metal, such as the computer?s case, so that any static build-up discharges.

Locate an empty PCI slot on the motherboard next to one that is already occupied by an SDRAMM card. At each end of the slot you will see an ejector tab/locking lever. Turn these outwards.

Handle you memory card carefully. Don?t flex or bend it and don?t handle the gold connector pins. The notches in the pin edge ensure that the card can only be inserted in the slot one way. Line the notch up with the keyway in the slot and push the card firmly down into the slot. The ejector tabs will close up automatically and lock the card in place.

That?s it. You?re done. Close up the computer and plug everything back in.

Upgrading your computer?s RAM is a simple and relatively cost effective way to give you more computer power. However there is a point at which additional RAM will not markedly improve performance if your processor is too slow. It pays to have as much RAM as your computer can cope with. Even when buying a new computer, it is worthwhile to include additional RAM with the purchase. For all your needs, use Myshopping.com.au to locate the right product and the best deal.