With DDR5 in the view, people might be thinking of waiting out on the purchase of memory. But DDR4 memory is still good and will be good for a while. People often argue what is a good DDR4 RAM, what affects its performance? Would buying more RAM equal better performance? What is this latency and speed? In this article, we will discuss DDR4 RAM speed vs latency.
So if DDR5 is going to become commercially available by this year’s end, why are we not saving for that instead? Because so far no CPU company has yet given support for DDR5 in their current line up of CPUs.
The word from AMD and Intel both is that this year’s lineup of CPUs from both companies will not have DDR5 support. They will probably work on that in their next year’s CPUs after all no one is suddenly going to opt for DDR5 right after its announcement.
So for now, we are using DDR4 speeds as standard to explain the two most important factors in memory modules. DDR4 RAM speed vs latency, which one to look out for the most.
The answer to that is a bit complicated than just declaring one of these the winner. To be honest, both of these factors matter equally and one is incomplete without the other.
Latency can be described as the time a device takes to input data, at least that is what it would mean in laymen terms. Like for instance, there is latency in wireless mice, although companies have almost zeroed out latency issues, there is still some of it present, even if it is as short as 1ms or lower.
When it comes to memory, it will be the number of clock cycles it takes for RAM to send the data over to the CPU which it has asked for. So basically you are feeding your CPU data through volatile memory, aka RAM. So in this case, the shorter the latency, the higher the performance.
The number of cycles a memory takes to find data and send it to CPU at blazing fast speeds is latency. It is happening so fast, you can barely tell the difference, but if there was a huge difference in latency, you would definitely note it.
But then what does speed mean? It is the total amount of cycles memory makes. If a memory module has a clock speed of 3200MHz, it means it will make 3.2 billion cycles per second. So the RAM is accessing its memory 3.2 billion times to find the data for the CPU to feed it.
A higher clock cycle speed will always equal better performance. Since it is called a dual data rate, the actual speed of a RAM is always half of what it is always shown. But since it transfers data twice per clock cycle, it is always mentioned double.
RAM Speed vs Latency
So if a memory module has 3200MHz speed, but it also has a CL of 20, and a 1600MHz RAM has 10 CL, they both are actually the same. Even under low performance, since there is half the latency, it means it is performing similar to the higher latency but also higher speed.
So in other words, a higher clock cycle and a shorter latency mean good performance. But the minimum CL of DDR4 is around 15, while DDR3 was good for 9-10 CL.
The CAS latency, which stands for Column Access Strobe Latency is the number of clock cycles passing when your CPU sends instructions to memory module’s particular column and the time in which it responds to it with the available data.
But a 3200MHz CL16 memory module has higher clock cycles than DDR3 and the latency is not double it means it is still better than the average DDR3 RAM. So DDR4 RAM these days are still performing better than the DDR3 with lower latency.
So regarding the argument, what should you focus on when buying a RAM, high speed or low latency, the answer is both. It will perform way better for you and always keep an eye on both of these before you purchase any memory module in the future.