Impact Of RAM Size And Speed On Gaming Performance

By CPUAgent Staff

Whether you’re planning your next build or have already gotten yours, knowing what RAM to get is essential to any PC enthusiast and can easily be overlooked by many. A good set of memory sticks can give you that extra push you need to reach your sweet 144 FPS or stabilize those annoying frame drops.

RAM size, speed, CAS Latency, and configuration, can all have significant effect on performance. A good pair of memory generally consists of 2 sticks of RAM, running in dual channel mode, with large capacity, high speed, and low timings and especially the CAS Latency.

RAM Size

Having too low RAM will certainly affect performance, but having too much will rarely improve it in most cases. Every video game or program requires a certain amount of memory to run properly, but once you go way beyond that amount, the rest of the RAM becomes almost useless in improving performance. In video games, that amount can also be affected by the graphics settings quality.

RAM size is the first and most important factor for better gaming performance. Games nowadays require at least 8GB of RAM, with 16GB being the recommended for most and for the overall use of a PC. The benchmark below shows the performance benefit of different RAM sizes at different resolutions.

The 4GB RAM suffered greatly because of both being low on capacity and being in single channel mode, which will be explained later here. The 8GB was able to run most games fine, but it can easily struggle when multi-tasking, such as browsing the internet with multiple tabs open. As for the 16 and 32GB, the results were very close, but since 32GB of RAM rarely gets fully utilized, we are left with 16GB as the best choice for price versus performance. Additionally, people who own motherboards with 4 RAM slots can always add more RAM should they desire so in the future.

Now that we established the recommended RAM size, let’s get into the other, more complicated factors.

RAM Speed/Frequency

RAM frequency is measured in cycles per second, and it plays a significant role in performance. A RAM with a frequency of 3600 MHz will perform better than a 2400 MHz one. To put things in perspective, we’re talking 3.6 billion cycles versus 2.4 billion cycles per second. For gaming, higher frequency means faster loading times because it allows the CPU to access the stored data more quickly.

In order to achieve the advertised speeds, first you need to have a motherboard that supports overclocked RAM, which is anything higher than 2666 MHz. Second, for motherboards with 4 RAM slots, the RAM stick(s) should be inserted into slots 2 and 4, counting from left to right. The actual names of those slots are A2 and B2, respectively. Finally, the RAM’s XMP (eXtreme Memory Profile) should be enabled from the motherboard’s BIOS settings.

RAM CAS Latency (CL) and Timings

CAS Latency, or CL for short, describes the clock cycles needed for the RAM to access and return a certain set of data from its columns to its pins, and the lower it is, the better. You may have come across 16GB RAM kits where one of them costs 80$ while another costs 110$. One of the reasons behind this price difference is the CAS Latency. The cheaper one could have CL18 while the more expensive could be CL14. Lower CAS Latency can make a lower speed RAM perform better than a higher speed one.

Memory timings consist of a series of 4 values, such as 16-19-19-39, which describe the CL, tRCD, tRP, and tRAS, respectively. The reason CL gets the most importance and advertising is because the rest of the values mostly depend on it. The lower they are, the better, but their dependence means they don’t have as much of an effect compared to CAS latency.

Single Channel versus Dual Channel configuration

If you ever went shopping for RAM before, then you have likely seen them sold in kits of 2, and for good reason. Having 2 identical RAM sticks on the motherboard will activate Dual Channel mode and increase memory transfer speed, resulting in better performance than a Single Channel memory. If your motherboard has 4 slots, it’s possible to have dual channel mode with 4 sticks (e.g. 4x8GB RAM) where each pair works in tandem. However, it’s better to go for 2 sticks instead of 4, because having more RAM sticks can add a bit more strain on the CPU controller, which in return might reduce the benefit of Dual Channel to begin with.

Performance Benchmarks

At this point, you should ask yourself a question: What type of games do I want to play, at what resolution, and at what FPS?

RAM with high speed and low CL will prove to be useful only in cases where you want (and can) achieve high frame rates, like 144 FPS or more. The type of game and the resolution greatly affect the achievable FPS averages too. For example, you can reach 144 FPS when playing most multiplayer games like Call of Duty: Modern Warfare or Battlefield V at 1080p, or even at 1440p if your rig is powerful enough or the settings are low enough. However, in some singleplayer games such as Assassin’s Creed: Odyssey, reaching 144 FPS at 1080p is hard enough even for powerful computers, let alone at 1440p or 4K.

The better your ram, the higher your FPS will be, but it is noticeable only when you can reach 100+ frames with your CPU/GPU combo. The benchmarks below show the performance benefit of different RAM frequencies at different resolutions.

At 1080p, we see a clear improvement in performance towards memories with higher speed and lower CL values. The 3600 MHz CL15 RAM holds a good position for its price and performance compared to the higher frequencies. The improvement is almost the same at 1440p, albeit the average FPS difference becomes less wide due to more strain being put on the GPU. However at 4K, the differences become negligible as most work is on the GPU alone. If you are aiming for 4K gaming, it’s better to invest more on a powerful graphics card.

One thing to note is that Ryzen processors tend to utilize higher speed RAM better than older Intel CPUs due to Ryzen being multi-threaded. That is, until recently when Intel released their 10th gen processers which do support Hyper-Threading. So, generally, try to go for RAM with 3600 MHz CL16 or better as they cost only a little more and can benefit you better.

Recommendations

If you’re looking for the best RAM in terms of price and performance, look for the following things:

  • A kit of 2 sticks of 8GB/16GB RAM (depending on the total RAM you desire)
  • Frequency between 3200 MHz and 3600 MHz
  • CAS Latency of 16 or lower

Here’s a couple of recommended RAM kits for you to consider:

3200 MHz

  • Team T-FORCE VULCAN TUF 16GB (2 x 8GB) 3200MHz with CL16 (16-18-18-38)
  • G.SKILL Flare X 16GB (2 x 8GB) 3200MHz with CL14 (14-14-14-34)

3600 MHz

  • G.SKILL Ripjaws V 16GB (2 x 8GB) 3600MHz with CL16 (16-19-19-39),
    • Or the more expensive one with lower timing of 16-16-16-36
  • G.SKILL TridentZ 16GB (2 x 8GB) 3600MHz with CL16 (16-19-19-39),
    • Or the more expensive one with lower timing of 16-16-16-36
  • CORSAIR Vengeance LPX 16GB (2 x 8GB) 3600MHz with CL14 (14-16-16-36)
  • G.SKILL Ripjaws V 32GB (2 x 16GB) 3600MHz with CL16 (16-19-19-39)