Welcome back to our series on the key hardware components in a computer. If you missed Part 1 of the series on CPUs, you can check that out here. But let’s jump right back into it this week, talking about RAM.

Random Access Memory (RAM or Memory)

When your CPU is doing work, it takes instructions from one place, does math, and sends the results to a place. When this happens billions of times each second, and when the results of one calculation may affect the next calculation, even having the place the instructions and results go to be 6 inches away would physically cause your CPU to be significantly limited in it’s total speed (If my math is right, which it may not be, it would put a hard limit on CPUs of somewhere around 1.97 GHz, compared to some boosting to speeds faster than 4.6 GHz currently).

So instead, a very small amount of this is handled extremely quickly within the CPU for extremely fast use, and most of this information is stored in the RAM just an inch away. The RAM is a place where information from a program, or from a file like a rendering or a CAD plan, can be stored for quicker retrieval than would be possible from a Hard Drive or Solid State Drive both due to the way the data is retrieved, and due to it’s physical proximity to the CPU. Four numbers come into play with RAM: the total capacity, the Speed in MHz, the number of DIMMS/SODIMM slots and how many RAM sticks are installed, and in a couple of years the Generation will come into play as well.

CAPACITY

The capacity of the RAM is, as you might expect, how much information it can hold. Having larger capacity is better, but depending on your use, at a certain point you will get diminishing returns to no additional value. RAM is shared among all software running, so some will be used by your Operating system (Windows), some by Firefox or whatever browser you might have open, Spotify might use some, etc.

Currently most systems will have at least 8 GB of RAM capacity. If you are doing a lot of multitasking (Having Spotify, several Chrome windows, Outlook, Word, Excel, Slack, Zoom, and maybe AutoCAD running all at the same time for instance) you may want 16 GB as a base-line. Or if you do more weighty work in something like AutoCAD, Photoshop, 3D Studio Max, or for gaming, occasionally there will be value in having 32 GB or more of RAM.

SPEED

The speed of RAM is measured in MHz. Generally RAM now is between roughly 2,000 and 4,000 MHz. And to make a long story short, higher is better.

If you’re building a computer the story gets messier, as each CPU is only rated to handle certain RAM speeds, and speeds above the 2133HMz that most RAM is clocked at by default will require an “XMP profile” to be enabled, adding additional voltage to your RAM to make it go the speed advertised on the box. Intel considers this to be overclocking your CPU under some arguably dubious reasoning, and they could void your warranty if you aren’t careful in what CPU, Motherboard, and RAM you use. AMD on the other hand has no issues with you using an XMP profile, but their current 3000 series processors only can use RAM up to 3600 HMz.

TIMINGS

Along with the raw speed, there are also the “timings” to consider when you look at RAM. These are numbers like “CL 16” or “15-16-16-35”. These are related to how many of those MHz it takes for specific things to happen, so a lower number is better. If you want a more in-depth explanation of how this works, Steve at Gamers Nexus does an amazing job explaining this in one of his videos HERE https://www.youtube.com/watch?v=o59V3_4NvPM But for the most part, if you see two types of RAM with the same MHz for the same price, but one has lower timings, that may be the one to get. Otherwise it will make a minor enough difference to most people that it isn’t something to lose sleep over.

DIMM/SODIMM SLOTS

Another thing to make note of, if you can find it, is how many DIMM (or SODIMM in a laptop) slots there are in a computer or on a motherboard. These are the physical slots the RAM slides into on the motherboard. You also want to know how many are taken. In some computers and many laptops there are two slots. Some computers will have four or more slots.

The reason this is important is two-fold:

1) If an even number of slots are taken up, assuming they are installed correctly, then the Memory will run in what’s called dual-channel, which is noticeably faster than single channel. So if you have two computers with 16 GB of 3200 MHz RAM, one as a single 16 GB stick, one as two 8 GB sticks, the one with 2 sticks will run significantly faster because it allows the memory to talk to the CPU through two channels instead of one.

2) You want to know because it will affect your ability to upgrade in the future. If you have 2 DIMM Slots and one 8 GB stick of RAM you can buy one more 8 GB stick, and move into dual-channel and also move from 8GB to 16 GB. However if you have two 4 GB sticks, it means it’s faster now because it will be dual-channel, but if you want to upgrade you need to buy two 8 GB sticks and get rid of the two 4 GB sticks you have.

DDR NUMBER

Lastly, in the coming years you’ll want to pay attention to what generation of RAM you are getting. Currently in 2020 almost all RAM available, and certainly all you should get, is DDR4. However the specifications for DDR5 were just finalized last year. None of the current motherboards or processors can use it, so it will likely be late 2021 or even 2022 before DDR5 is something you can buy and use.

CONCLUSION

For most people, 8 GB of RAM should be the target on a desktop or laptop, ideally as two sticks of 4G each to have them run in dual channel. However people who are doing work with large files, or graphics work, or for Gaming, 16 GB may give better performance. 32 GB or more might be needed by people who do really large files- video or very high resolution photography, but for most people it won’t be much benefit. Even for Gaming 16 GB tends to be enough, with the new Microsoft Flight Simulator 2020 being only the second game to say that it would be ideal to have 32 GB of RAM.

RAM should likely cost you somewhere in the neighborhood of 8-12% of a PC build unless you have pressing needs that would mean you need a larger capacity or higher than usual speed.

With the CPU and Memory covered, next time we will dive into the next key component- Graphics Cards.

If you have a question about any of the information I’ve given, or about something I haven’t addressed, let me know in the comments below or on my About page, and I’ll try to answer your question, or I may even turn it into more content- There are things I may not realize I need to talk about until you tell me. Thanks!