Computer Memory

The first thing you'll want to look at when building yourself a computer is what type of case you want to buy. It's important to have a clear idea of what kind of system you want and what components are required to build that system before deciding on a case since you need to be sure all your computer components will fit in the case. The type of case you choose will depend on your specific needs for that particular machine.

There are a few different types of memory currently in popular use; they are usually referred to by their acronyms, and this can confuse the uninitiated so we will briefly describe each of the types of computer memory.

SDRAM (Synchronous Dynamic Random Access Memory)

This type of memory was revolutionary a few years ago and is now the most common type of memory found in desktops, but the technology is now outdated. You can still get decent performance if you get lots of SDRAM but I'd recommend getting one of the newer types at least for compatibility reasons if not for the performance increase. The newer processors require the newer memory types such as DDR-SDRAM or RDRAM to achieve the intended performance levels.

DDR-SDRAM (Double Data Rate Synchronous Dynamic Random Access Memory)

This is an improvement on SDRAM and as its name suggests it is twice as fast; its maximum transfer rate is about 1064 MBps as opposed to about 528 for standard SDRAM. Unfortunately a DDR memory module is not compatible with a standard SDRAM module; a DDR DIMM has 184 pins and requires 2.5 volts while SDRAM DIMMs have 168 pins and require 3.3 volts.

RDRAM (Rambus Dynamic Random Access Memory)

RDRAM is a different technology altogether from SDRAM and DDR-SDRAM. If you are buying a new Pentium 4, this is probably the type of RAM you will choose, and possibly the only one supported by your motherboard. It's more expensive than the other types but faster as well, achieving a data rate of 1600 MBps.

Older Types of RAM

There are a couple of other types of RAM you might run across that you should steer clear of as they are almost certainly too slow for your purposes. DRAM stands for Dynamic Random Access Memory and its maximum throughput is only 50 MHz. EDO DRAM offers about a 5% performance increase over DRAM, but this still isn't enough, and even if it was the technology is virtually obsolete.

Reading this will hopefully have demystified computer memory somewhat for you. Remember that these days it's not so much the type of memory you get as it is the quantity. If you can find some older SDRAM at a great price, and your motherboard will support it, you'll have that much more cash to spend on a video card.