Buying Memory/RAM: What to Know

First, let’s get something out of the way. By “memory” I’m referring to volatile memory. Volatile memory, or Random Access Memory (RAM), deals with the actively-running applications on your computer, while non-volatile memory is found in a hard drive (or an SSD). While you wouldn’t technically be wrong to call the space on your hard disk “memory,” usually people refer to their drive capacity as storage and their amount of RAM as, well, memory. So that’s what memory means in the context of this article.

There are multiple factors to take into consideration whenever you’re buying RAM. Namely, these factors are:

  • type of RAM
  • RAM capacity
  • RAM frequency

If you’re new to this, that may have sounded like a bunch of babble. Worry not! Read on, and I’ll explain everything.

RAM Types


As laid out in the image above, there are four main types of RAM. These standards are, as follows:

  • DDR RAM. Beyond obsolete, very unlikely to find a machine running on it (or RAM sticks using it).
  • DDR2 RAM. Obsolete, but not quite out of the wild yet. Many older desktops and laptops use DDR2 RAM, though laptop RAM is a discussion for later.
  • DDR3 RAM. The current standard, supporting frequencies over twice as fast as DDR2 and higher capacities. Also cheaper than DDR2 RAM at the same capacities.
  • DDR4 RAM. The latest standard, though buying machines with DDR4 support can cost a pretty penny. Frequencies start at DDR3’s high end of 2133, capacities can go even higher, and, due to being a newer standard, DDR4 is better-priced at the same frequencies and capacities than its DDR3 counterpart.

Let’s take a moment to talk about these different standards. First and most obviously, yes, the lower the DDR designation, the slower and more expensive the RAM is. This is especially applicable when comparing DDR2 prices to DDR3, and remains noticeable with DDR4 vs DDR3, though to a lesser degree.

In addition, each implementation of DDR RAM has a higher capacity than the one preceding it. While the limits of DDR2 and onward would be very hard to reach for the common user, the increased capacity of each generation means that, along with the boost in speed and power, buying high-capacity RAM from a newer generation is cheaper than buying it from an old one. We’ll go more into capacity later, however.

For now, let’s talk about what memory your motherboard supports.

If you’re making a new computer build, you should at least get a motherboard with support for Dual-Channel DDR3 RAM. You can get DDR4, too, if you feel inclined to future-proof yourself.

If you’re simply upgrading your existing RAM, however, you’re going to need to identify what type of RAM your motherboard supports. To do this, find what model your motherboard is. On Windows, open up Start and then type “System Information.” You should be given the name of your System Manufacturer and System Model there. On prebuilt laptops and desktops, this information can typically be found on the hardware itself – once you’ve identified your system’s make and model, a simple Google search will let you find out what motherboard is inside, or at least what type of memory is compatible with it.


Laptop RAM

For laptop users, this also applies. You’ll need to consult your computer’s model number to learn what kind of RAM is compatible with it. Note that a laptop RAM upgrade usually costs more than desktop RAM. This is usually due to laptop RAM’s smaller form factor and, sometimes, the age of the computer. To find RAM upgrades available for your laptop without doing all the busywork, consider using a Memory Finder tool – Newegg, TigerDirect and Crucial all have good tools for that.

RAM Capacity


A commonly-quoted line from Bill Gates is “640K memory ought to be enough for anyone.” Unfortunately for people who like to quote it, Bill Gates never actually said that, and for good reason, since RAM needs have greatly evolved over time. What I’m writing now, however, should be generally applicable for at least another five years, so let’s get into it.

  • 512 MB of RAM to 1 GB of RAM. Disgusting, unless you’re running a machine from the 90s/early 00s. That was actually good. By modern standards, however, it definitely won’t cut it.
  • 2GB of RAM. Fairly modest. Will result in some very noticeable hitches in multitasking, especially when using multiple browser tabs, never mind multiple applications at once.
  • 4GB of RAM. Decent. Shouldn’t be too bad at all, actually. Plus, now you’re in 64-bit operating system territory. Enjoy your performance boost but know your limits!
  • 8GB of RAM. Great. Even with heavy gaming and multiple tabs and applications, you shouldn’t find yourself bothered by noticeable slowdowns at all. At the moment, 8GB of RAM should service everyone just fine, though recent games are starting to require 6GB as a baseline.
  • 16GB of RAM. Hoo boy. Are you running a Virtual Machine or something? Or do you just want to look cool?
  • 32GB of RAM. Okay, son. You need to stop. Unless this is a server we’re talking about, in which case that’s cool, I guess.
  • 64GB+ of RAM. Either you’re running a server or you’re completely insane. In either case, I like you.

Note that at the time of writing – late 2015 – we’ve yet to see games or applications start to demand more than 8GB RAM out of our machine. With the passing of time, however, we’ll undoubtedly see applications that can take advantage of more RAM. Let us know if that time has passed and this starts to seem outdated.

RAM Frequency


RAM’s frequency is measured in Megahertz, or MHz. You may recognize MHz as the measurement used by processors from the olden days, but don’t worry about it; RAM performs fairly well at most frequencies in the DDR2-3 range, and especially well in the high-end DDR3 and DDR4 ranges. Let’s take a moment to talk about the types of RAM again and what their frequencies actually mean.

  • DDR RAM unfortunately only supports two frequencies – 333MHz and 400MHz. Let’s just disregard that for now.
  • DDR2 RAM is much, much more flexible. It was the first major step forward in volatile memory and supports frequencies starting at 400MHz all the way up to 800MHz. This is a big deal, all things considered!
  • DDR3 RAM starts off at 1066MHz and goes all the way up to 3200 MHz, albeit at the cost of a severe price hike. Enthusiasts typically stop around the 2133 MHz mark.
  • DDR4 RAM starts at 2133 MHz and goes all the way up to a whopping 4266 MHz. MHz is becoming a redundant measurement at this point. Actually, you may better recognize DDR4’s peak frequency as 4GHz, which is higher than most commercial processors.

As far as the actual speed of the memory goes, this shouldn’t matter in most scenarios. The generational leap between DDR and DDR2 was immense, and DDR2 is fine for most common usage purposes. DDR3 is great for them and for gaming, and while higher frequencies of DDR3 and DDR4 may factor into real, tangible leaps in performance in the future, at the moment nothing really takes advantage of that potential.


The short version is the newer it is, the better (and generally cheaper) it is, at least where RAM is concerned.

Anything I left out? Any other questions you might have? Sound off in the comments, and let me know what you need!

Christopher Harper
Christopher Harper

I'm a longtime gamer, computer nerd, and general tech enthusiast.

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