Memory

Description:

All programs, instructions, and data must be stored in system memory before the computer can use it. It will hold recently used programs, instructions, and data in memory if there is room. This provides quick access (much faster than hard drives) to information. The more memory you have, the more information you will have fast access to and the better your computer will perform.

Memory is much like the short term memory in your brain. It holds your most recent information for quick access. Just as you want to accurately remember this information in your head, you want your computer's memory to have the correct information as well, or problems will obviously occur. Bad memory is one of the more common causes of computer crashes, and also the most difficult problem to diagnose. Because of this, making sure you get good RAM the first time around is very important. My Recommendations will help you get the fastest, highest quality RAM you can.

There are many, many different types of memory for different tasks. The main ones today are DDR PCxx00 SDRAM DIMMs (this includes PC2700, PC3200, etc.) and Direct RDRAM RIMMs.

What To Look For:

In the following discussion I will focus on memory for motherboards (main system memory).

First you need to know the type of memory you need. RDRAM RIMMs are only used in some Pentium IV motherboards. They have a higher bandwidth than other types of memory, but surprisingly enough they don't usually perform much better than regular DDR SDRAM (it also costs a lot more). DDR SDRAM is what's used in AMD Athlon XP motherboards (and many Pentium IV motherboards now too).

The type of RAM can usually be determined just by the motherboard's chipset. Below is a simple table of what RAM type (max speed RAM) should be used for each motherboard chipset (only recent chipsets are listed and I have bolded the chipsets I recommend):

Intel i875 (P4) PC3200 (DDR 400) Intel i865 (P4) PC3200 (DDR 400) Intel i850 (P4) PC1066 RDRAM Intel i848 (P4) PC3200 (DDR 400) Intel i845 (P4) PC2100 (DDR 333) Via KT600 (AMD Athlon XP) PC3200 (DDR 400) Via KT400A (AMD Athlon XP) PC3200 (DDR 400) Via KT400, KT333 (AMD Athlon XP) PC2700 (DDR 333) Via KT266A (AMD Athlon Thunderbird) PC2100 (DDR 266) Via P4X400 (Intel P4) PC3200 (DDR 400) Via P4X266 (Intel P4) PC2100 (DDR 266) NVIDIA nForce 2 Ultra 400 (AMD Athlon XP) PC3200 (DDR 400) SiS 748 (AMD Athlon XP) PC3200 (DDR 400)

RAM speeds are also something to consider. Here's a table of the actual speeds of common types of DDR memory (with my recommendation in bold):

Memory type: Actual Speed: DDR Speed: PC3200 (DDR400) 200 MHz 400 MHz PC2700 (DDR333) 166 MHz 333 MHz PC2100 (DDR266) 133 MHz 266 MHz

CAS 2 or CAS 3 is a very important consideration with SDRAM for speed reasons. Getting CAS 2 can speed up your computer and also allow for higher overclocking speeds.

Many other timing numbers are important, but they are often misrepresented and confusing so I won't get into them too much.

Unbuffered and Non-Parity are words you generally want to hear. Don't worry if your memory says this.

The brand of the RAM chips as well as the brand of the PCB (the memory board) are both very important. Low quality chips or low quality PCBs can both cause problems. Good chips on bad PCBs is just the same as getting bad chips. It would be a good idea to buy memory from the manufacturer so you can be sure the chips and PCB are by the same manufacturer.

Recommendations:

Today's motherboards use DDR SDRAM or RDRAM (on some Intel motherboards only). RDRAM is expensive and the performance isn't much better in general use. Please note, for dual channel DDR RAM, you need two sticks of memory.

Corsair XMS memory is my number one pick. However, it's expensive compared to other brands. This memory is great for overclocking and getting low latency speeds, helping your computer to run faster. I would suggest PC3200 CAS 2 memory (C2). The specific model number is CMX512-3200C2 which has timings of 2-3-2-5-T1. Corsair's regular memory (not the XMS line) is also good and cheaper.

I recently started using Kingston's Hyper-X memory, which is a high performance memory at a reasonable price. I've been very happy with it and think it would be a great choice.

Crucial makes high quality, reliable memory, but it isn't always the fastest. At the time of this writing, they don't even have PC3200 memory available that runs at CAS2. It can be a little pricey, but their support, return policies, and free shipping make them a good choice.

A couple of newer companies to consider are OCZ Technology and Geil. These are both manufacturers of high performance memory, but I haven't used it much myself. Many users have been very happy with these manufacturers, although some have had problems with Geil (while others have been very happy with it).