Ram Slots 1-3 Vs. 2-4 | What Should You Choose?

It is a long-discussed debate among the PC enthusiast, and there are a lot of opinions regarding whether to insert the RAMs in slots 1 and 3 or slots 2 and 4?

There is not much difference between the RAM slots, and different types of motherboards have different kinds of RAM slot properties. Usually, the difference between them lies in the channel optimization and the RAM frequency, also known as XMP.

The RAM slot recommendation and specification depends upon the motherboard, and most of the time, the RAM slots 2 and 4 are dual-channel in contradiction to slots 1 and 3, which are single channels.

This article will discuss the difference between slots 1,3 and 2,4 and what you should choose when building the PC.

Don’t forget to check out our separate post for Best RAM for i5 9600K.

The Purpose Of RAM

To understand what pair of the RAM slot would be better and why first, we must know the purpose of RAM. RAM is the abbreviation of Random Access Memory, and they are used to store the volatile storage of the current working tasks. With more powerful RAM, more task memory can be stored and accessed, and as a result, the program will run faster.

In modern computers, more than one RAM is used to have much more memory that enables them to execute more tasks more smoothly.

Check out our separate post for 3 Pin Vs. 4 Pin Fan Connector.

Slot Mechanism

Now that we have understood the purpose of RAM, it is time to understand the slot machine. Most motherboards have 4 RAM slots nowadays, out of which two are single-channel, and two are dual-channel.

The primary difference between the single-channel support and the dual-channel support is the data transfer rate that plays a crucial role in the RAM and the processor. The RAM sends the data through the motherboard received by the RAM slot to go to the processor.

The specification of the RAM slot is essential in that case because it is the pathway by which the data is transferred. Please think of the supercar that can reach 250 mph; the car can not reach its full potential until it is provided with an empty road.

Similarly, the working of the RAM and the processor is based on how much data they can send and receive, and RAM slots are a significant contributor to that.

Performance Difference Of RAM Slot

The RAM slots 1 and 3 are generally single channels, whereas the RAM slots 2 and 4 are dual channels. To understand the performance difference of the RAM slot, first, we have to discuss the term Bandwidth.

The term Bandwidth you might have heard multiple times, usually in terms of the internet transfer rate. It is the unit of the data transfer in all computing and electronic devices and is measured in the MB per second (MBps) or GB per second (GBps).

The same goes for the RAM; most modern RAMs have DDR technology which means that they can send two bits of data in a single clock cycle that doubles the data transfer rate.

Dual-channel support is ideal and necessary if you want your system to its full potential. The bus width of the system also matters in this case, and it is essential to know your system’s bit capacity.

It can either be 64-bit or 32-bit. The memory can not cross the maximum limit of the Bandwidth, so if you have installed the 3000 MHz DDR RAM in the single rate slot, then the system’s Bandwidth can be found using the formula.

Bandwidth = clock rate x data bus width / 8

If you use the 3000 MHz data bus RAM with or without overclocking with the 64-bit system, then.

            Bandwidth = (3000 * 64) / 8

            Bandwidth = 24000 MBps


            Bandwidth = 24 GBps

If you use the dual-channel RAM slot, the data transfer rate would be increased by increasing the wires in the slot. This directly impacts the bus width system, and the 64-bit system will now behave like a 128-bit system by the dual-channel support.

With this, the Bandwidth of the RAM would be doubled, and the RAM that produced the Bandwidth of 24 GBps will now transfer the data at the rate of 48 Gbps.

Also, check out our separate post for Best RAM for Ryzen 7 2700x.

Impact On Working

If you are an experienced gamer, you will recognize the game quality drop by using a single channel RAM slot instead of the dual channel RAM slot. The dual-channel RAM slots can provide 60 to 100 FPS to tier 1 game compared to 50 to 80 fps in single-channel RAM slots.

The critical thing to note here is that these frame rates heavily depend upon the CPU and GPU requirements, and the number is for the comparison.

Dual-Channel & Quad Channel Slots

The basic idea is that when you are using the single RAM stick, it will run on a single channel system, and when you are using two RAM sticks, they will run on a dual channel system. From this point of view, if you install 4 RAM sticks, they should run on a quad-channel system.

This may or may not be the case, and it depends upon the motherboard and CPU specification whether they support quad-channel support.

It is ideal to utilize the two RAM slots by dividing the required memory into two rather than installing a single powerful RAM. This will increase the Bandwidth and, ultimately, the PC’s performance.

Test Between Single Channel And Dual Channel

We used the two RAM sticks of DDR4 3000 MHz of 8 GBs and used them one by one on the RAM slot 1,3 and RAM slots 2,4. Following games were played to test the performance of the RAM and the RAM slot.

  • Pubg
  • GTA 5
  • Dirt 4
  • Shadow of war
  • Middle Earth

The results were shocking and astonishing at the same time. Most of the time, the FPS of the game did not drop as expected but rather maintained at a level comparable in both of the tests. Although, there was a difference in CPU usage, and it was 10 to 25 percent in the single-channel slot than in the dual-channel space.

From the results, it can be predicted that using the RAM slot 1 and 3 might not directly impact the game’s performance, but still, it matters in the CPU performance.

Also, check out our separate post if you don’t know what should be your normal CPU temperature while gaming.

How To Fill RAM Slots?

The best strategy to fill the RAM slots is to buy two identical RAMs and place them in RAM slots 2 and 4. It is better to buy 2 RAMs rather than a single powerful RAM because they will provide a better data transfer rate and Bandwidth.

There is no point in using 3 or 4 RAM sticks if you are using them on a dual channel motherboard. If you have spare RAM, you can place it in RAM slot 1 or 3, but it would not make much difference.

For the best performance and minimum price, use two RAMs. Using one RAM might be cost-effective, but it would limit the performance. Using four RAMs will be costly and would not make much difference.

This is a rule of thumb for filling the RAM slots.

  • Slot 2
  • Slot 4
  • Slot 1
  • Slot 3


Using the RAM lost 2 and 4 is better than using the RAM slot 1 and 3. This is not just the belief and the theory, but experimental results also suggest the same. The dual-channel memory slot doubles the RAM bandwidth so that there is faster data transfer than in the single-channel space. It is mainly due to more wires in the dual-channel place.

In general, it is observed that the RAM performance directly impacts the Frame rate of the game, but in actual practice, we did not find any such observations; this may be due to the internal hardware performance and the CPU and GPU settings.

But still, the FPS did not drop. Instead, there was an extra load on the CPU usage in the single-channel slot, and it was observed that 25 percent more CPU was used.

Frequently Asked Questions

Which Is Better, RAM slot 1 and 3 or RAM slot 2 and 4?

RAM slots 2 and 4 are better because they offer dual-channel memory support. The dual-channel system doubles the Bandwidth and the data transfer rate, which enhances the system capabilities, and as a result, the gaming quality improves.

Can I use RAM slots 3 and 4?

Slot 4 is a dual-channel, and slot 3 is a single channel, so basically, you are just limiting the performance efficiency of your RAM stick by putting it into the wrong slot. It is better to use RAM slots 2 and 4.

Can I use three slots for RAM?

Yes, but using the 3 RAM slots would not triple the RAM performance unless your motherboard has quad-channel support. Using 3 RAM slots means that two of them go in the dual-channel slots that are 2 and 4, and the third will go in the single-channel space that is either 1 or 3.
You will only get about 20 percent of the memory performance and the Bandwidth, and in most of the games, it is negligible because two RAMs are enough for most of the gaming needs.

Mubeen Shahjahan
Mubeen is from Pakistan and he has been playing video games since the age of 10. He got into this gaming craze because it was just one way that his creative mind could explore and grow without boundaries, but now as an adult, Mubeen finds enjoyment not only in those initial adventures stories; they serve more than ever before-they provide motivation to achieve goals both big (like getting good enough at something) or small like overcoming fear when climbing stairs for the first time!