Your system’s RAM must be one of the top priorities on your mind if you’re creating or updating it. The RAM, in the opinion of the majority, speeds up the processor. Contrary to popular belief, Random Access Memory, or RAM, essentially prevents the system from performing to its fullest capability. This is due to the fact that the CPU will always be faster than the RAM, forcing the processor to wait for the RAM to provide the data. The CPU is idle throughout this waiting period, wasting both time and energy.
Recent technological developments have attempted to break through the speed barrier by switching to multiple, triple, and even quad-channel approaches to boost speed, with dual channel being the most prevalent. However, how big of an increase does it actually result in? To determine whether the buzz around Dual Channel is true or not, and to determine whether the upgrade is really worthwhile, we will compare Single Channel vs Dual Channel Memory modules today. But first, let’s take a look at how a system’s memory truly functions.
How Memory Works
TheRAM
A memory controller circuit in the system is in charge of controlling memory.
Single Channel vs Dual Channel Memory: Architecture
A network of cables generally referred to as a Memory Bus connects the RAM and the Memory Controller. These wires have now been further separated into the Control, Data, and Address groups. The memory modules, which contain details about the type of operation the system is carrying out, receive commands from the Control wires. Data that is either being read from the memory to the memory controller or written from the memory controller to the memory will be carried across the data wires.
The memory speeds (or clock rates) for the aforementioned memory module are likewise determined by the memory controller. For instance, even if you instal a 2400 MHz memory module, if the Memory Controller specifies that the maximum clock rate it supports is 1333 MHz, the system will only be able to use that maximum speed, underclocking the RAM. Now that you know the fundamental workings of a RAM, let’s compare Single Channel vs Dual Channel Memory.
A single stick of RAM may push data down to a single pipe that is a total of 64 bits wide since it operates on a single 64-bit data channel. The single channel memory’s architecture is depicted below. Single Channel Architecture
That being said, nowadays, modern systems support multi-channel platforms as well. In the case of Dual Channel Memory, the system makes use of not one but two memory channels. Now, we have got2 64-bit channelsavailable to the memory. This means we ve doubled the data traces running on the memory bus, and now have aneffective 128-bit channel. Dual Channel Architecture
Bandwidth
If you take a closer look at the image above, you ll see that both the channels support data bit ports from D00 to D63, that is, 64 ports. That being said, effectively, the ports on the channel 2 are taken from D64 to D127, thus emulating the next set of 64 ports. As a result, thesystem regards the channel width to be a total of 128-bit widthrather than 64-bit. Effective Dual Channel Architecture
As you can see above, the D0-D63 represent the first channel, D64-D127 represent the second channel. Thus, modules can process 64 bits of data at any given time, and sodual-channel platforms will read and writeto two modules simultaneously (saturating the 128-bit wide bus).
Bandwidth is themaximum theoretical transfer rateof a communications channel and is measured in megabytes per second (MB/s) or gigabytes per second (GB/s). Current technologies such as DDR (Double Data Rate) can transfer two data bits per clock cycle. As a result, they achieve double the transfer rate compared to traditional memory technologies. For example, the DDR3-1333 MHz module may actually be working at 666.6 MHz, but transferring two data bits per clock cycle. Furthermore, bandwidth also depends upon the width of the data bus. A single channel makes use of a 64-bit device width, which basically means that 64 bits of data are transferred at each transfer cycle. Thus, theoretically, bandwidth can be calculated as:
bandwidth = DDR clock rate x data bus width / 8
So, for a single channel DDR3-1333 Memory, the theoretical bandwidth comes out to be
Bandwidth in Single Channel = 1333 x 64 / 8 =10,664 MB/s or 10.6 GB/s
Newer technologies such as dual channel technologiesfocus on doubling the data bus widthby increasing the number of data wires available in the memory bus. A dual channel makes use of 128-bit device width, ie, 128 bits of data are transferred at each transfer cycle (as shown in the architectural differences above). This, in turn, impacts the system by theoretically doubling the bandwidth. For example, for a dual channel DDR3-1333 Memory, the theoretical bandwidth on calculation comes out to be
Interleaving
Bandwidth in Dual Channel = 1333 x (64 x 2) / 8 =21,328 MB/s or 21.3 GB/s
Note:While the difference between the bandwidths is staggering, do keep in mind that this is just a theoretical calculation of the two values. Actual performance between Single Channel vs Dual Channel memory may differ, which is discussed further.
Interleaved memory is a design made tocompensate for the relatively slow speedof Dynamic Random-Access Memory (DRAM) or core memory. This is done by spreading the memory addresses evenly across memory banks. The memory bank consists of multiple columns and rows of storage units spread across several chips. Each memory module can have two or more memory banks for program and data storage.
Benchmarks
Interleaved memory results incontiguous read and writes.
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Euler 3D
This actually uses each memory bank in turn, instead of using the same one repeatedly. Eventually, it results in significantly higher memory throughput as each bank has a minimum waiting time between reads and writes. Interleaving Memory Read and Write
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MaxxMem Copy, Read, Write, and Bandwidth
Usinga Dual Channel Memory increases the number of memory banks, thus, in turn, improving the interleaving design to result inbetter multitasking.
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MaxxMem Memory Latency
While benchmarking is not equivalent to real life performance, it is far more realistic than the theoretical calculation. As such, we compared aSingle Channel Corsair Vengeance 8GB DDR3 RAMwith aDual Channel Corsair Vengeance 8GB (4 2 kit) DDR3 RAM, both costing the same $64.99. The following benchmarks were conducted on our test machine.
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Handbrake Video Transcoding
In our Euler 3D Benchmarking, the Dual Channel Memory configuration performedapproximately 17% betterthan the Single Channel Memory configuration. The difference between the two puts the Dual Channel Memory ahead of its competitor. This advantage should prove to be useful for users carrying out heavy-duty computation, simulation, and compilations.
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Adobe Premiere Encoding Pass
Upon our tests with MaxxMem, we tested the memory copy, memory read, memory write, and memory bandwidth performances. These tests are measured in Megabytes per second. As such, we saw significant performance differences between the Single Channel vs Dual Channel Memory modules, with the Dual Channel having a clear lead in each case. That being said, it is worthy to point out that the performance is no way near to the theoretical calculation, considering the bandwidth should have been doubled when instead we observed a~20% booston average.
Real Life Performance
Latency refers to the delay before a transfer of data begins following an instruction for its transfer. In our memory latency test on MaxxMem, we found that there was amere ~2.7%differencein the latencies, with the Dual Channel memory module still performing slightly better than the Single Channel.
On our Handbrake Benchmarking, we saw almost a4.5% advantagein favor of Dual Channel Memory. That being said, Handbrake in itself is a really powerful tool, that pushes the system to its limits. Even for most heavy-duty users who do video ripping or transcoding, the slight difference wouldn t make much of a difference.
For video editing, Adobe Premiere is one of the most demanding software out there. In our benchmarking test, we found that the Dual Channel setup saves approximately8 secondsin overall rendering time, thus giving it the slight edge. While the difference here is quite insignificant, for systems that render all day long, the rendering time gap could prove to be bigger, thus saving a few crucial minutes off the shelf.
Single Channel vs Dual Channel Memory: Which One Is Better?
While the above benchmarks proved to be in slight favor of the Dual Channel Memory module, in my real life usage, I found there to be anegligible differencebetween the two. Pages loaded slightly faster and my software such as iTunes, Google Chrome, and Microsoft Office ran at equivalent speeds. And yes, I made sure to clear the cache before testing each Memory setup to ensure precise results.
Additionally, I also ran some games to test their performances. The results are shown in the graph below. Gaming Benchmarks FPS Higher is better
Single Channel vs Dual Channel Memory: What s Better For You?
We tested the Dying Light, Metro Last Light, Grand Theft Auto V, and The Witcher 3: Wild Hunt on our system when paired up with theMSI NVIDIA GTX 1060. The results were more or less the same, with the Dual Channel having aslight advantageover the Single Channel memory modules. That being said, there were cases where the Dual Channel mode experienced performance drops, which was quite evident in the Witcher 3. Even so, the difference between the two is still negligible whatsoever.
To summarize, I d say that yes, in the comparison of Single Channel vs Dual Channel Memory, Dual Channel does come out as the winner. That being said, the benchmark and real life results are way different from the differences that were calculated on paper. Theoretically, there should have been a 2x difference, while in reality, the Dual Channel seems to exhibit only a16-17% advantageat best in overall usage. While attaining a difference of 12-13% is also desirable, it is certainly not worth the hype that surrounds Dual Channel Memory. In most cases, the normal user would not even notice the difference between the two. And as far as power users are concerned, even though Dual Channel does come out on top, theywould not be sacrificing anything significant.
SEE ALSO:DDR3 vs DDR4 RAM: Is It Worth The Upgrade?
