For computer processors, “dual-channel” refers to a CPU configuration that allows for two data streams to be read from and written to at the same time. In other words, dual-channel RAM runs two data streams in parallel, which can result in faster response times than single-channel RAM. For most computers with DDR3 RAM, you’ll see either “RDIMM” or “LRDIMM” listed on the processor specifications. These acronyms refer to different types of DRAM modules known as registered vs. Load Reduced DIMMs. Again, these terms refer to different ways that the SDRAM chips are packaged within the module. They don’t make any difference in performance or functionality of your computer. The following article explains these differences and tells you how you can identify if your computer has dual-rank or single-rank RAM:
What is Dual-Rank RAM?
RAM modules come in different sizes and with varying numbers of chips per module. The number of chips per module—as well as the way those chips are connected—determines the “rank” of a DRAM module. A dual-rank DRAM module has two ranks. A single-rank DRAM module has one rank. The rank refers to the number of electrical pathways connecting one chip to another. In a dual-rank module, one rank is dedicated to receiving data and another rank is dedicated to sending data. Dual-rank modules are ideal for use in dual-channel DDR3 systems because they allow data to be accessed simultaneously from both ranks. The dual ranks are wired in series, forming a single data path used by the CPU to address both ranks simultaneously.
What is Single-Rank RAM?
A single-rank DRAM module only has one rank. This means the module has only one series of pathways connecting one chip to another. Single-rank modules are ideal for use in single-channel DDR3 systems because they allow data to be accessed from only one rank at a time. This means the CPU can only address one rank at a time, even if it has two data streams that it needs to process simultaneously. The single rank is wired in parallel with a second rank. This forms two data paths used by the CPU to address two ranks simultaneously.
How to Identify Dual-Rank RAM
You identify dual-rank RAM by reading the processor specifications and looking for the term “RDIMM.” RDIMM stands for Registered Dual In-line Memory Module. These are typically 16-chip modules that contain a pair of ranks. RDIMMs are ideal for use in dual-channel DDR3 systems because they allow data to be accessed simultaneously from both ranks. If the processor’s specifications show “UDIMM” instead of “RDIMM”, the computer is single rank.
How to Identify Single-Rank RAM
You identify single-rank RAM by reading the processor specifications and looking for the term “UDIMM.” UDIMM stands for Unregistered Dual In-line Memory Module. These are typically 10-chip modules that contain one rank. UDIMMs are ideal for use in single-channel DDR3 systems because they allow data to be accessed from only one rank at a time. UDIMMs are usually available in two varieties: standard and low-voltage. Standard UDIMMs operate at 1.5V while low-voltage UDIMMs operate at 1.2V.
When buying computer RAM, you need to make sure that you are buying the correct type of memory. You also need to be sure that the type of memory you buy has enough capacity to meet your computer’s needs. If you’re not sure what type of RAM your computer has or you need to upgrade your memory, the information in this article should help you to identify what type of RAM your computer uses.