After a lot of research, you decided to build your first PC all alone! You have bought all the components, making sure they are compatible with each other, and now it’s time to put everything together.
And when it is time to plug in the RAM, you realize you have no idea which slots to use and find yourself asking questions like:
Which RAM slots should I use? Is there a certain order in which I should use the RAM slots? What happens if I put the sticks in the wrong slots?
First things first, let me tell you that it does matter which slots you use, especially if you are using two or more RAM sticks.
If you want to know why it does matter, which RAM slots you should use and why, and some geeky stuff about RAM, keep reading.
does it matter Which RAM slots I use?
Before talking about which slots you should use, let me explain why and when it does matter which RAM slots you use.
The truth is that if you use only one RAM stick, it doesn’t really matter in which slot you will plug it (of course, you should check the motherboard manual for the best results). But if you are planning to use more than one stick, it matters a lot because of the “multi-channel memory architecture.”
And I am sure many of you would wonder what that thing is and why you should care about it, so let me explain it as simply as I can.
The multi-channel memory architecture is a technology that helps you achieve higher data transfer rates. It works by using multiple 64-bit data channels simultaneously, making the communication between the CPU and the memory faster. The most common multi-channel architecture for home computers is the dual-channel, but some motherboards support triple-channel or quad-channel. At his point, I would like to mention that because you are using a dual-channel architecture, it doesn’t mean you will get double the speed. In most cases, you will get around a 20-30% speed increase. But why leave it on the table when all you have to do is to plug the RAM sticks in the right slots?
Related Article: “Does RAM Affect FPS? [Solved]“
Which RAM slots should I use?
And now, it is time to answer the question that brought you here in the first place: Which RAM slots to use?
The answer is not that straightforward, as many factors influence the outcome, but to keep things simple, let’s say that your motherboard supports dual-channel memory and has four RAM slots (This is the most common setup on modern motherboards).
1 Memory Stick
The first thing you should do, no matter the number of memory sticks you will use, is to look at the motherboard manual. More often than not, with just one memory stick, the RAM slot doesn’t matter. This is because you will not use dual-channel mode, so the performance will be the same no matter which slot you use (In older motherboards, you were supposed to use to slot closest to the CPU, but this is not the case anymore). In my opinion, you should use slot number 4 (the one further away from the CPU socket), as you will have more room between the RAM stick and the CPU cooler, reducing the heat generated.
2 Memory Sticks (Matched Pairs)
I might sound boring, but again the first thing you should do is check the motherboard manual. The general rule of thumb is to put the matched pairs in the same colored slots, and in 99% of the cases, the RAM pairs should go either into slots 1 and 3 or 2 and 4. At this point, I wanted to mention that manufacturers usually use dual-channel memory in slots 2 and 4 and single-channel memory in slots 1 and 3. So make sure to check your motherboard manual and if this is the case with your motherboard, put the RAM modules in slots 2 and 4.
3 Memory Sticks
I will not tell you what you should do, as you should know by now (spoiler alert check the motherboard manual). What you want to check is if your motherboard supports triple-channel memory (which is pretty rare). If it doesn’t and you are going to use three RAM sticks on a dual-channel architecture, put the two sticks as you would on a dual-channel configuration (slots 2 and 4) and use the third one in the slot between them (slot number 3).
4 Memory Sticks
With four slots and four sticks, there is not much to say. All you have to do is to put the first pair of sticks in slots 2 and 4 and the second pair in slots 1 and 3.
Related Article: How Long Does RAM Last? [Solved]
What if your motherboard has more than four slots?
If you have a motherboard with more than 4 slots, it means you have a server-grade motherboard, and you should know what you are doing. I am not going into full detail, but the general rule is to know the capabilities of your motherboard (does it support dual-channel memory, triple-channel, or quad-channel memory?) and to put the matched pairs in the appropriate slots according to the motherboard’s manual.
Related Article: 16GB vs 32GB RAM: How Much Do You Really Need?
How to check if you have installed the RAM sticks correctly
After you have plugged in the RAM sticks, you should check if your system is actually using dual-channel memory. The best way to do that is to use CPU-Z.
CPU-Z is a free monitoring tool where you can see several things about your computer hardware.
First, visit CPU-Z’s official website and download it. After installing and running it, click on the “Memory” tab next to the “Mainboard” tab and look at the number of channels. If it says “Single”, you have screwed something up, and you have to unplug the RAM sticks and start over. If it says “Dual”, you have done everything right, and you can enjoy the performance increase.
RAM Slots FAQ
Does it matter which 2 RAM slots you use?
Yes, if your motherboard has more than two slots, then you will have to put the sticks in the proper RAM slots to be able to take advantage of the dual-channel memory.
Which RAM slots to fill first?
Before deciding which RAM slots to fill, you should check the motherboard manual. But as a general rule of thumb, motherboard manufacturers tend to make the number 2 and 4 dual-channel RAM slots and the number 1 and 3 single-channel mode RAM slots. This means that if you want to reap the benefits of dual-channel memory, you should first fill the number 2 and 4 slots and then the number 1 and 3 slots.
Can you put RAM in slots 1 and 3?
Yes, you can put RAM in slots 1 and 3; just make sure to check the motherboard manual to see if they support single or dual-channel memory.
Can I use all 4 RAM slots?
Yes, you can use all 4 ram slots, but it is important to use sticks that are of the same capacity and speed. RAM compatibility is very tricky, and if you use many sticks, you should know what you are doing, or you might end up with an unstable system.
Can you mix RAM speeds?
Yes, technically, you can mix RAM speeds, but it is not advisable. The reason is that if you use different speed sticks, your system will use the slower stick’s speed across all slots, slowing down your computer.
How do I know if my RAM is dual-channel?
To know if your RAM is dual-channel, you should use a software like CPU-Z. As mentioned above, after downloading and installing CPU-Z, go to the memory tab and check the number of channels.
As you can see, which RAM slots you will use is really important as it can increase or decrease your system’s performance. Read your motherboard’s manual and use the dual-channel RAM slots for the best performance.
I hope this article helped you learn how to install RAM; if you have any questions, feel free to ask them in the comment section below.
Nick Ryley is a computer architect and the owner of The Pc Geekz.
His love for playing games got him interested in computers in the first place. He wanted to be able to build a gaming PC that could run all the latest games at max settings, and this has him pursuing a major in computer architecture!
He started this blog to help people out and answer some of the most common questions about computer building