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There are a few questions about RAM that are quite frequently asked:

  • What types of RAM are there out there?
  • Which type is right for me?
  • How fast does my RAM need to be?
  • How much RAM should I get?
  • What brands are the best?


There are generally two types of RAM for AMD computers, with sub-types.

SDRAM (Synchronous Dynamic Randomly Accessed Memory):

It comes in 168-pin DIMMs-(meaning that it will work with only one stick installed…stands for Dual Inline Memory Module). SDRAM is not compatible with DDR or RDRAM. (In other words, don’t try to put a stick of SDRAM in a DDR slot–it won’t fit.)

There are to basic types of SDRAM:

PC 100: Slow and old. Hardly ever seen today, but it still exists. I would never recommend buying this. It runs at a frequency of 100MHz
PC 133: The standard in SDRAM technology. It runs at 133MHz and is not fast. Only get this if you’re forced to by your motherboard.

Now, on to the second type of RAM:

DDR RAM (Double Data Rate Random Access Memory):

This is the mainstream of RAM today for both sides of the fence–AMD and Intel both use this in their current chipsets. Very low latency and fairly high frequency, this type of RAM is the best option for anyone building a machine today. DDR RAM comes in 184-pin DIMMs and is not compatible with SDRAM (In other words, don’t try to put a stick of DDR in an SDRAM slot–It won’t fit.)

As with SDRAM, DDR RAM comes in different speeds:

PC1600: Rarely seen today, PC1600 DDR runs at 100MHz and is at the lowest end of the spectrum for speed in DDR technology.
PC 2100: This used to be the standard for speed in DDR technology, but with higher speed processors, this has been pushed to the low end. It runs at 133MHz and is fairly quick RAM.
PC 2700: This is the standard for DDR RAM today. It runs at 166MHz and is quite fast.
PC 3200: This RAM is very fast and is the standard for overclockers. It runs at 200MHz and is very fast. * Note: Any of the 200MHz FSB CPUs will work best with PC3200 RAM (3200+ Barton)
PC 3500: This RAM is near the top end of the spectrum and runs at very high front side buses.
PC 3700: Hard to find, and extremely fast.
PC 4000: Recently released, next to impossible to find, but it’s top notch.

Now, you ask, why is DDR faster than SDRAM? Well, DDR reads twice per clock cycle while SDRAM only reads once per clock cycle. It makes DDR more efficient and therefore faster even at the same frequencies.

Which type is right for me?

The easy answer is DDR. The only exception to this rule would be if you have a SDRAM only board. Nearly all boards (with the exception of a decent amount of budget boards) that can be bought today use DDR technology.

How fast?

For most anyone, PC 3200 would be the highest that you would need to go. I would go with no less than PC 2700 right now for a couple of reasons. RAM is cheap. PC 2100 will hinder your ability to upgrade your CPU and still have a synchronous FSB / RAM clock.

How much RAM should I get?

This has to be one of the most frequently asked questions about building computers – bar none. For almost anyone, 512MB will be absolutely fine. Even you gamers and Photoshop gurus will be generally happy with 512MB. 256MB is pushing it as today’s operating systems are becoming even more of a memory hog. For basic use, sure, 256MB will do. 1024MB (1GB) of RAM should be reserved for those who have the money to blow or those who are doing a lot of CAD / 3D Studio Max / Maya work. Anything more than 1GB is overkill (for now…I won’t fall into the “640Kb is all you will ever need” scenario).

What brands of RAM are the best?


Building an AMD Based Computer System - Systems 20

The undisputed champion of the DDR RAM world: Corsair XMS.

This is another one that I hear quite often. I’ll make this pretty simple and lay it out flat. The best brands out there are as follows: Corsair XMS, TwinMOS, Mushkin, Xtreme DDR, Samsung, and Crucial (Micron). In my opinion, Corsair is king. They are the fastest and most stable, period. TwinMOS, while not very well known, has had a growing reputation among overclockers for a while now. Their PC 3200 sticks are said to rival Corsair. Mushkin used to be the top dog, but has fallen from the picture a bit lately as Corsair has gained the advantage. Another not-to-well-known company, Xtreme DDR, has been making great RAM for a while now. Samsung and Crucial seem to be the “reliable” companies for RAM, but they aren’t great at overclocking.

Current popular Memory options:

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