The correct posture of dual channel memory is like this...

This year's good memory gains have already broken through the bottom line of many NNNN partners and the memory prices have more than doubled. However, there is a demand for a small partner to buy it or buy it, Xiao Bian predicts that the second half of next year is expected to ease, if you wait to use it then do not hesitate to buy early to use early. On the other hand, many people are always asking Xiaobian about the problem of upgrading memory, especially Xiaobian always advocates dual-channel memory. However, it does not seem to complete the whole with everyone to talk about the dual-channel memory formation method, especially the different capacity, different number of memory combinations with dual-channel, Xiaobian today specifically talk about this matter.

What is a flexible dual channel?

First of all, we must talk about Intel Flex Memory Technology. This technology can make the memory more flexible. It allows dual channels with different capacities, different specifications and even unpaired memory, allowing system configuration and memory upgrade. More flexible (Note: AMD has similar technology).

Specifically, for example, the symmetric dual channels in the middle of the figure below are AB and AB methods. The two channels, A and B, read and write memory. When the dual instructions are requested at the same time, the AB channel is used to read and write memory at the same time. It is also possible to issue a request assuming that the A instruction requests to go out without returning a B instruction. The right-most is the asymmetrical dual-channel working mode diagram. Assuming a dual-channel system consisting of 1GB and 512MB of memory, 512MB of memory will be split in 1GB of memory and dual-channel with another 512MB of physical capacity. The remaining 512MB of memory in 1GB of memory has access to data in a single channel, which is elastic (asymmetric) dual-channel memory.

The difference between memory slots

Now to talk about the difference between memory slots, in fact, there is no flexibility in the early years of dual-channel memory, memory must be in pairs, the same capacity (the speed can be different, whichever is the slowest). Therefore, in the design of the motherboard, the memory slot has been used to distinguish the channels of the memory slots by color, and it has become a habit as time goes by. Of course, there are now some motherboards that have broken this design for overall beauty, using a uniform color scheme. But need to pay attention to, although we are accustomed to memory slots from the CPU side to say memory slots 1,2,3,4, but actually in the design of the motherboard, the memory slot should be identified in the small picture - - 1, 3, 2, 4 pairs.

How many dual channel combinations?

Well, understand these, we will say today's focus! How to group two channels, Xiao Bian is divided into three situations.

1, two memory

The simplest case is two memories, which are divided into the same capacity and different capacities. The simplest of the same capacity, regardless of any kind of installation method, as long as you talk about two of the same capacity of memory inserted into the motherboard, you can achieve dual-channel, and test performance performance is almost no difference!

The same is true for different capacities, such as the combination of different capacities of 8GB+4GB. However, Xiao Bian suggested that it is best to follow the order, A1 + A2 (1 + 3), B1 + B2 (2+4) installed in a paired installation - this is because when the CPU memory controller query always There will be a sequence.

2, three memory

The situation of three memory is relatively rare, but it is not absent. In the same capacity, sequential installation is possible; if it is different in capacity, it is better to use A1+A2, B1 or B2 to install the third one with different capacity; or conversely, B1+B2 to install the same capacity, A1 Or A2 installs the memory of different capacity. what? Are all three different? Hey, is this really okay? The answer is of course useable, but this is very rare.

3, four memory

Four memory and three memory is almost the same situation, the difference is that after all, four memory, in fact, it does not matter ... Of course, the best memory is still the same capacity in pairs.

Is there a difference in performance?

Different combinations, performance is naturally different. Two-channel memory more than ten years ago, two memory performance is the best, but after more than ten years of development, the best performance is now four-memory dual-channel capacity, followed by the same capacity two memory dual The passage is roughly the same.

In particular, it is important to note that many test software cannot properly test dual-channel combinations of different capacities, as well as dual-channel memory combinations with different amounts of memory. Test results will look similar to single-channel memory, and do not care. Just look at the software such as CPU-Z to view the memory property as Dual on it.

In addition to the memory throughput changes seen in the test results, the most intuitive effect is still when using the core graphics card. Because it is dual-channel memory, the performance of the core graphics card will have a relatively large increase. In addition, large-capacity, high-speed dual channel memory performance is significantly faster when decompressing WinRAR and rendering graphics images.

In addition to dual-channel memory technology, there are actually four-channel memory technology, which consists of four channels (or eight) of four channels to further improve memory data access capabilities. However, only four-channel memory controllers are integrated at the server- and workstation-level processors because they require more memory bandwidth.