Computer Memory Speed and Latency

Memory Speed The velocity of the reminiscence will decide the rate at which the CPU can technique information. The better the clock score at the reminiscence, the faster the gadget is capable of examine and write data from the reminiscence. All reminiscence is rated at a particular clock fee in megahertz that the reminiscence interface talks to the CPU with. Newer memory classifying techniques at the moment are beginning to consult them based at the theoretical facts bandwidth that the reminiscence helps which can be difficult.

Memory Speed Types of Memory Speeds

All the variations of DDR reminiscence are stated through the clock rating, but more frequently memory producers are starting to refer to the bandwidth of the reminiscence. To make things confusing, those reminiscence kinds may be indexed in ways. The first technique lists the reminiscence by its basic clock speed and the version of DDR that is used. For instance, you may see mention of 1600MHz DDR3 or DDR3-1600 which basically is just the type and the rate blended.

The other technique of classifying the modules is by their bandwidth score in megabytes according to second. 1600MHz reminiscence can run at a theoretical pace of 12.Eight gigabytes in keeping with 2d or 12,800 megabytes consistent with second. This is then prepended by means of the version wide variety appended to PC. Thus DDR3-1600 memory is likewise referred to as PC3-12800 memory. Here is a brief conversion of a number of the usual DDR memory that may be discovered:

  • DDR3-1066 = PC3-8500
  • DDR3-1333 = PC3-10600
  • DDR3-1600 = PC3-12800
  • DDR4-2133 = PC4-17000
  • DDR4-2666 = PC4-21300
  • DDR4-3200 = PC4-25600

Now it is also essential to recognise what the maximum speed of memory that your processor can support. For example, your processor may additionally simplest aid as much as 2666MHz DDR4 reminiscence. You can nonetheless use 3200MHz rated reminiscence with the processor but the motherboard and CPU will modify the speeds all the way down to successfully run at 2666MHz. The end result is the memory is run at much less than its full potential bandwidth. As a result, you want to buy reminiscence that great suits your laptop’s capabilities.


For reminiscence, there’s every other issue that affects the performance, latency. This is the amount of time (or clock cycles) it takes the memory to reply to a command request. Most pc BIOS and memory manufacturers listing this as both the CAS or CL rating. With each technology of reminiscence, the range of cycles for command processing is growing. For instance, DDR3 generally runs among 7 and 10 cycles. Newer DDR4 has a tendency to run at almost two times that with latency jogging among 12 and 18. Even though there are higher latency with the more moderen reminiscence, other elements inclusive of better clock speeds and improve technologies usually do no longer cause them to slower.

So why will we mention latency then? Well, the decrease the latency the quicker the reminiscence is to respond to instructions. Thus, reminiscence with a latency of say 12 will be better than similar speed and technology reminiscence with a latency of 15. The problem is that most purchasers will no longer surely notice any benefit from the decrease latency. In truth, faster clock velocity memory with slightly better may be a bit slower to reply but provide a tremendous quantity of memory bandwidth that could provide better performance.