Memory Channels
16 GB, DDR2 1200(O.C.)/1066./800/667 ECC,Non-ECC,Un-buffered Memory Dual Channel memory architecture.We recommend that you install the DDR2 1200 memory modules on the yellow slots for better performance.Due to AMD CPU limitation, DDR2 1200(O.C.)/1066 is supported by AM3/AM2+ CPU for one DIMM per channel only. I know that different types of ram (DDR1, DDR2. Etc) Have different color slots to tell the difference between them, my question is what color corresponds to which.? Such as (from what i think.
In the fields of digital electronics and computer hardware, multi-channel memory architecture is a technology that increases the data transfer rate between the DRAM memory and the memory controller by adding more channels of communication between them. Theoretically this multiplies the data rate by exactly the number of channels present. Dual-channel memory employs two channels.
Single-channel (asymmetric) mode
This mode provides single-channel bandwidth operations and is used when only one DIMM is installed or when the memory capacities of more than one DIMM are unequal. When using different speed DIMMs between channels, the slowest memory timing is also used.
Single Channel memory, with a maximum rated clock of 400 MHz and a 64-bit (8 bytes) data bus is now becoming obsolete and is not being produced in massive quantities. Technology is adopting new ways to achieve faster speeds/data rates for RAM memories.
Dual-channel architecture
Dual-channel-enabled memory controllers in a PC system architecture utilize two 64-bit data channels. Dual channel should not be confused with double data rate (DDR), in which data exchange happens twice per DRAM clock. The two technologies are independent of each other and many motherboards use both, by using DDR memory in a dual-channel configuration.
Dual-channel
architecture requires a dual-channel-capable motherboard and two or more DDR, DDR2 SDRAM, or DDR3 SDRAM memory modules. The memory modules are installed into matching banks, which are usually color-coded on the motherboard. These separate channels allow the memory controller access to each memory module. It is not required that identical modules be used (if motherboard supports it), but this is often recommended for best dual-channel operation.
Motherboards supporting dual-channel memory layouts typically have color-coded DIMM sockets. Coloring schemes are not standardized and have opposing meanings, depending on the motherboard manufacturer's intentions and actual motherboard design. Matching colors may either indicate that the sockets belong to the same channel (meaning that DIMM pairs should be installed to differently colored sockets), or they may be used to indicate that DIMM pairs should be installed to the same color (meaning that each socket of the same color belongs to a different channel). The motherboard's manual will provide an explanation of how to install memory for that particular unit. A matched pair of memory modules may usually be placed in the first bank of each channel, and a different-capacity pair of modules in the second bank.[6]
Modules rated at different speeds can be run in dual-channel mode, although the motherboard will then run all memory modules at the speed of the slowest module. Some motherboards, however, have compatibility issues with certain brands or models of memory when attempting to use them in dual-channel mode. For this reason, it is generally advised to use identical pairs of memory modules, which is why most memory manufacturers now sell 'kits' of matched-pair DIMMs. Several motherboard manufacturers only support configurations where a 'matched pair' of modules are used. A matching pair needs to match in:
- Capacity (e.g. 1024 MiB). Certain Intel chipsets support different capacity chips in what they call Flex Mode: the capacity that can be matched is run in dual-channel, while the remainder runs in single-channel.
- Speed (e.g. PC5300). If speed is not the same, the lower speed of the two modules will be used. Likewise, the higher latency of the two modules will be used.
- Same CAS Latency (CL) or Column Address Strobe.
- Number of chips and sides (e.g. two sides with four chips on each side).
- Matching size of rows and columns.
Dual-channel architecture is a technology implemented on motherboards by the motherboard manufacturer and does not apply to memory modules. Theoretically any matched pair of memory modules may be used in either single- or dual-channel operation, provided the motherboard supports this architecture.
Performance
Theoretically, dual-channel configurations double the memory bandwidth when compared to single-channel configurations. This should not be confused with double data rate (DDR) memory, which doubles the usage of DRAM bus by transferring data both on the rising and falling edges of the memory bus clock signals.
Tom's Hardware found little significant difference between single-channel and dual-channel configurations in synthetic and gaming benchmarks (using a 'modern (2007)' system setup). In its tests, dual channel gave at best a 5% speed increase in memory-intensive tasks.[7] Another comparison by Laptop logic resulted in a similar conclusion for integrated graphics.[8] The test results published by Tom's Hardware had a discrete graphics comparison.
Another benchmark performed by TweakTown, using SiSoftware Sandra, measured around 70% increase in performance of a quadruple-channel configuration, when compared to a dual-channel configuration.[9]:p. 5 Other tests performed by TweakTown on the same subject shown no significant differences in performance, leading to a conclusion that not all benchmark software is up to the task of exploiting increased parallelism offered by the multi-channel memory configurations.[9]:p. 6
Ganged versus unganged
Dual-channel was originally conceived as a way to maximize memory throughput by combining two 64-bit buses into a single 128-bit bus. This is retrospectively called the 'ganged' mode. However, due to lackluster performance gains in consumer applications,[10] more modern implementations of dual-channel use the 'unganged' mode by default, which maintains two 64-bit memory buses but allows independent access to each channel, in support of multithreading with multi-core processors.[11][12]
'Ganged' versus 'unganged' difference could also be envisioned as an analogy with the way RAID 0 works, when compared to JBOD.[13] With RAID 0 (which equals to 'ganged' mode), it is up to the additional logic layer to provide better (ideally even) usage of all available hardware units (storage devices, or memory modules) and increased overall performance. On the other hand, with JBOD (which equals to 'unganged' mode) it is relied on the statistical usage patterns to ensure increased overall performance through even usage of all available hardware units.[11][12]
Triple-channel architecture
Operation
DDR3 triple-channel architecture is used in the IntelCore i7-900 series (the Intel Core i7-800 series only support up to dual-channel). The LGA 1366 platform (e.g. Intel X58) supports DDR3 triple-channel, normally 1333 and 1600Mhz, but can run at higher clock speeds on certain motherboards. AMD Socket AM3 processors do not use the DDR3 triple-channel architecture but instead use dual-channel DDR3 memory. The same applies to the Intel Core i3, Core i5 and Core i7-800 series, which are used on the LGA 1156 platforms (e.g., Intel P55). According to Intel, a Core i7 with DDR3 operating at 1066 MHz will offer peak data transfer rates of 25.6 GB/s when operating in triple-channel interleaved mode. This, Intel claims, leads to faster system performance as well as higher performance per watt.[14]
When operating in triple-channel mode, memory latency is reduced due to interleaving, meaning that each module is accessed sequentially for smaller bits of data rather than completely filling up one module before accessing the next one. Data is spread amongst the modules in an alternating pattern, potentially tripling available memory bandwidth for the same amount of data, as opposed to storing it all on one module.
The architecture can only be used when all three, or a multiple of three, memory modules are identical in capacity and speed, and are placed in three-channel slots. When two memory modules are installed, the architecture will operate in dual-channel architecture mode.[15]
One of the differences between DDR, DDR2 and DDR3 is the highest transfer rate each generation can reach. Below is a list the most common speeds for each generation.
DDR memory's primary advantage is the ability to fetch data onboth the rising and falling edge of a clock cycle, doubling thedata rate for a given clock frequency. For example, in a DDR200device the data transfer frequency is 200 MHz, but the busspeed is 100 MHz.
DDR1, DDR2 and DDR3 memories are powered up with 2.5,1.8 and 1.5V supply voltages respectively, thus producing lessheat and providing more efficiency in power management thannormal SDRAM chipsets, which use 3.3V.
Temporization is another characteristic of DDR memories.Memory temporization is given through a series of numbers,such as 2-3-2-6-T1, 3-4-4-8 or 2-2-2-5 for DDR1. Thesenumbers indicate the number of clock pulses that it takes thememory to perform a certain operation—the smaller the number,the faster the memory.
The operations that these numbers represent are the following:CL–tRCD–tRP–tRAS–CMD. To understand them, you haveto keep in mind that the memory is internally organized as amatrix, where the data is stored at the intersection of the rowsand columns.
- CL: Column address strobe (CAS) latency is the time it takes between the processor asking memory for data and memory returning it.
- tRCD: Row address strobe (RAS) to CAS delay is the time it takes between the activation of the row (RAS) and the column (CAS) where data is stored in the matrix.
- tRP: RAS precharge is the time between disabling the access to a row of data and the beginning of the access to another row of data.
- tRAS: Active to precharge delay is how long the memory has to wait until the next access to memory can be initiated.
- CMD: Command rate is the time between the memory chip activation and when the first command may be sent to the memory. Sometimes this value is not informed. It usually is T1 (1 clock speed) or T2 (2 clock speeds).
| igure 2: SMAC in Numbers | ||||
| Memory | Technology | Rated Clock | Real Clock | Maximum Transfer Rate |
| PC66 | SDRAM | 66 MHz | 66 MHz | 533 MB/s |
| PC100 | SDRAM | 100 MHz | 100 MHz | 800 MB/s |
| PC133 | SDRAM | 133 MHz | 133 MHz | 1,066 MB/s |
| DDR200 | DDR-SDRAM | 200 MHz | 100 MHz | 1,600 MB/s |
| DDR266 | DDR-SDRAM | 266 MHz | 133 MHz | 2,100 MB/s |
| DDR333 | DDR-SDRAM | 333 MHz | 166 MHz | 2,700 MB/s |
| DDR400 | DDR-SDRAM | 400 MHz | 200 MHz | 3,200 MB/s |
| DDR2-400 | DDR2-SDRAM | 400 MHz | 200 MHz | 3,200 MB/s |
| DDR2-533 | DDR2-SDRAM | 533 MHz | 266 MHz | 4,264 MB/s |
| DDR2-667 | DDR2-SDRAM | 667 MHz | 333 MHz | 5,336 MB/s |
| DDR2-800 | DDR2-SDRAM | 800 MHz | 400 MHz | 6,400 MB/s |
| DDR3-800 | DDR3-SDRAM | 800 MHz | 400 MHz | 6,400 MB/s |
| DDR3-1066 | DDR3-SDRAM | 1066 MHz | 533 MHz | 8,528 MB/s |
| DDR3-1333 | DDR3-SDRAM | 1333 MHz | 666 MHz | 10,664 MB/s |
| DDR3-1600 | DDR3-SRAM | 1600 MHz | 800 MHz | 12,800 MB/s |
Single Vs Double Sided ram
In SDRAM single sided (high density) can be used only in modern PCs. Old PCs don't always read the memory right because they calculate how much RAM to access based on the number of chips on the stick, not taking into account that each chip might contain twice the storage.
So for old PCs you should use double-sided (low density) RAM to ensure that it will work correctly in your system. Otherwise, the PC might end up convinced that your memory has only half the storage capacity that it is actually capable of.
To my knowledge, in SDRAM there is no real performance difference between the two. (Unlike with RDRAM which increases latency by the number of chips, so high-density is slightly faster than low-density.) So any modern PC that can properly use the single-sided (high density) SDRAM should be happy with whatever combination that you use.
Several types of memory modes can be configured on Intel® Desktop Boards, depending on how many memory modules (DIMMs) are installed:
Single-channel (asymmetric) mode
This mode provides single-channel bandwidth operations and is used when only one DIMM is installed or when the memory capacities of more than one DIMM are unequal. When using different speed DIMMs between channels, the slowest memory timing is also used.
Single-channel with one DIMM
Single-channel with three DIMMs
At boot, the memory configuration is detected and you might see this alert message:
Alert: Maximum memory performance is achieved with equal amounts of memory installed in each channel. Press any key to continue.
With the DIMMs that are currently installed, the computer is set to single-channel mode, but it can be set to dual-channel mode. If you shut down and rearrange the DIMMs properly, you can establish dual-channel mode.
Dual-channel (interleaved) mode
This mode offers higher memory throughput and is enabled when the memory capacities of both DIMM channels are equal. When using different speed DIMMs, the slowest memory timing is used.
Dual-channel with two DIMMs
Dual-channel with three DIMMs
Dual-channel with four DIMMs
Rules to enable dual-channel mode
To achieve dual-channel mode, the following conditions must be met:
- Same memory size. Examples: 1 GB, 2 GB, 4 GB.
- Matched DIMM configuration in each channel
- Matched in symmetrical memory slots
Configurations that do not match the above conditions revert to single-channel mode. The following conditions do not need to be met:
- Same brand
- Same timing specifications
- Same speed (MHz)
The slowest DIMM module populated in the system decides memory channel speed.
Triple-channel mode
Triple-channel interleaving reduces overall memory latency by accessing the DIMM memory sequentially. Data is spread through the memory modules in an alternating pattern.
Three independent memory channels give two possible modes of interleaving:
- Triple-channel mode is enabled when identical matched memory modules are installed in each of the three blue memory slots.
- If only two of the blue memory slots are populated with matched DIMMs, dual-channel mode is enabled.
Quad-channel mode
This mode is enabled when four (or a multiple of four) DIMMs are identical in capacity and speed, and are put in quad-channel slots. When two memory modules are installed, the system operates in dual-channel mode. When three memory modules are installed, the system operates in triple-channel mode.
Quad-channel with four DIMMs:
Quad-channel with eight DIMMs:
Flex mode
This mode results in both dual and single-channel operation across the whole of DRAM memory. The figure shows a flex mode configuration using two DIMMs. The operation is as follows:
- The 2 GB DIMM in slot 1 and the lower 2 GB of the DIMM in slot 2 operate together in dual-channel mode.
- The remaining (upper) 2 GB of the DIMM in slot 2 operates in single-channel mode.
We’ve spent hundreds of hours researching and comparing Ddr2 Sdram of all specifications to find the best one for any need (or budget). Here are the results.
Contents
- 3 Ddr2 Sdram Reviews on Twitter
The Best Ddr2 Sdram of 2020 – Top Rated & Reviewed
2,086 Reviews Scanned
Rank No. #1 Komputerbay 4GB Kit (2GBx2) DDR2 800MHz (PC2-6400) CL6 SODIMM 200-Pin 1.8v Notebook Laptop Memory Modules with Lifetime Warranty- 4GB KIT OF 2 ( 2 X 2GB ) DDR2 SODIMM 800Mhz PC2-6400 / PC2-6300 200PIN
- WORKS ON ALL COMPATIBLE LAPTOPS THAT ACCEPT 2GB 800MHZ SODIMMS. Non-ECC Non parity
- Voltage 1.8V. SUPPORTS DUAL CHANNEL
- Lifetime Warranty
- Jedec Standard configuration 256X64
- 2GB DDR2 DIMM
- 240-Pins Desktop Memory
- Non-ECC, Non-Register
- 16Chips Low Density
- Life-time Warranty
- 4GB 2X 2GB DDR2 800MHz PC2-6300 PC2-6400 DDR2 800 (240 PIN) DIMM Desktop Memory
- 100% Compatible with Desktops
- 2x2GB PC2-6300 PC2-6400 DDR2 800 Mhz. Supports Dual Channel
- Compatible with desktops that support DDR2 240 pin memory
- Lifetime Warranty
- Please Note: DDR2 sdram may not work on all devices. Please check your device's specifications before purchasing. Such as RAM model, RAM slot and maximum memory of your computer. If not sure, we are glad to help you here.
- Compatibility: AMD, Intel (PC2-6400/DDR2 800 1.8V CL6 2RX8 Dual Rank 240 Pin UDIMM)
- HI-Q Chip: Hynix, Kingston, Samsung, Micron, ELPIDA, Nanya and Qimonda.
- Strict Test: Compatibility tested across all popular brands of motherboards for fast performance; 100% hand test before shipping out.
- Worry-Free Warranty : Life-time warranty for your confident purchase. Any problem about DDR2 sodimm, please feel free to contact us at tecmiyo@163.com, we’ll provide you friendly and easy-to-reach support.
- Komputerbay Apple 4GB Kit (2x 2GB Modules) PC2-5300 667MHz DDR2 SODIMM iMac and Macbook Memory
- This memory is designed for the following systems: iMac Intel Core 2 Duo 17-inch CD (Late 2006), iMac Intel Core 2 Duo 20-inch (Mid 2007)
- iMac Intel Core 2 Duo 24-inch (Mid 2007), MacBook Pro 15.4-inch 2.2GHz/2.4GHz/2.6GHz, and MacBook Pro 17-inch 2.4GHz/2.6GHz
- Compatible with macs that support 4GB DDR2 200PIN memory
- Lifetime Warranty
- Dear customer before purchase please ensure ram model, max memory and ram slot. Before installation please clean connection figure gently with eraser and clean out the slots with canned air, don’t use corrosives like ethyl alcohol.
- pc2 5300 8gb support DDR2 667MHZ desktop,PC2-5300 240 Pin unbuffered Non ECC, 1.8V CL5 2Rx8 Dual Rank .
【Compatibility】DDR2 PC2-5300 great compatible with AMD,Intel systems.
【HI-Q Chip and Strict Test】Hynix, Kingston, Samsung, Micron, ELPIDA, Nanya and Qimonda. Extensively tested at the component and function level. Ensure the quality of each DDR2 667 ram.
- 【Life-time Warranty】If for any reason you're not completely satisfied with our ddr2 ram 2gb Memory, please don't hesitate to contact us at kuesuny@163.com.
Ddr2 Slot Colors
- Memory Chip: All DUOMEIQI chips are from big brand manufacturers such as Micron, Hynix, Samsung, Kingston, ELPIDA, Nanya and Qimonda, a high level of reliability.
- Note: Please confirm your computer model and the correct memory parameters as well as the maximum memory of each slot， to prevent the trouble of returning due to a wrong purchase.
- ✅Multifunction: Increase bandwidth, improve system performance, reduce power consumption and extend battery life. Faster burst access speed for improved sequential data throughput, bring you great online and game experience.
- ✅WARRANTY SERVICE: Life-time warranty for your confidence purchase. Any problems, please feel free to contact us at yaimay@163.com , we are here for you 24 hours.
- ✅Due to different production batches, chips from different brands will be used. Meanwhile even the same brand chips, will not be totally same, chips color and parameters maybe some different. Please be assured, all chips have been through strict tests to ensure a high quality.
- Capacity: 4GB 2 X 2GB Kit FULLY BUFFERED DIMM FB LOW POWER MEMORY
- Form Factor: 240 pin DIMM
- Warranty: Lifetime
- ONLY FOR THE SERVER LISTED
- DO NOT BUY FOR STANDARD DESKTOPS WHICH USE NON-ECC MEMORY
- Superior Compatibility: DDR2-800 MHz PC2-6400 8GB Kit (4x2GB) 240-pin NON-ECC Unbuffered Desktop Memory. With strong compatibility and high stability with motherboards of various brands.
- High-Quality and Strict Test: Motoeagle's memory use high quality chips (Samsung, SK Hynix, Kingston, Micron). All chips 100% Tested, RoHS Compliant, JEDEC Compliant. Provide your computer with superior memory quality and the stability required for long-term system operation.
- Plug and Play: Memory upgrade is one of the fastest, easiest, and most affordable ways to immediately improve the performance of your computer. It can improve your computer system performance, reduce power consumption and extend battery life. Faster burst access speed for improved sequential data throughput, bring you great online and game experience.
- Lifetime Warranty and Toll Free Technical Support: If for any reason you're not completely satisfied with our ddr2 ram 800mhz 2gb udimm memory, please feel free to contact with us at motoeagle-service@hotmail.com
- Attention: Before purchase, please ensure your computer ram model, max ram and ram slot. Before installation, please wipe connection finger gently with eraser.
- Model: ddr2 pc2-5300 ddr2 667 udimm ram, 2RX8 240 Pin Non-ECC Unbuffered Desktop ddr2 sdram. (Before purchase, please ensure RAM model, max memory and RAM slot. Before installation, please clean connection figure gently with eraser.)
- ✅Memory Chip: Each 2gb ddr2 ram is from big brand manufacturers such as Micron, Hynix, Samsung, Kingston, ELPIDA, Nanya and Qimonda, a high level of reliability.
- ✅Connecting Finger: Advanced electroplating process is applied on the connecting finger of pc2 5300 ddr2 667mhz ram to improve corrosion resistance and electrical conductivity.
- ✅Multifunction: This ddr2 ram 4gb kit will increase bandwidth, improve system performance, reduce power consumption and extend battery life. Faster burst access speed for improved sequential data throughput, bring you great online and game experience.
- ✅WARRANTY SERVICE: Life-time warranty for your confidence purchase of this ddr2-667 udimm ram. Any problems, please feel free to contact us at yaimay@163.com , we are here for you 24 hours.
Top Rated Ddr2 Sdram to Buy Now
Ddr2 Sdram Reviews on Twitter
[custom-twitter-feeds search=”Ddr2 Sdram”]
Why You Should Buy Best Ddr2 Sdram from Amazon
Ddr2 Slot Coloring Pages
Amazon is not the only store that sell Ddr2 Sdram. However, there are several compelling reasons why you should buy Ddr2 Sdram from them, with the suitable Price and Reviews. Here are five:
(1) Amazon Makes Shopping Ddr2 Sdram Personal
Amazon is very good at making recommendations of Ddr2 Sdram based on your search history. From time to time, they will even show you discounted prices on Ddr2 Sdram that you previously expressed an interest in. They also make your shopping experience a little easier by showing you items that you recently viewed.
(2) Amazon Checkout is Easy
Amazon checkout is easy, especially if you already have an account. You can add Ddr2 Sdram to your cart and go through a multi-step checkout process, or you can buy Ddr2 Sdram with only one click by using your stored credit card information.
(3) Amazon Has Lots of Social Proof
Before you make a purchase for Ddr2 Sdram, you want to know that the company you are dealing with is legitimate and that others trust the company enough to make a purchase. You may also like to read what others are saying about the product in the review section. Amazon does all of this quite well.
(4) Amazon Has Great Ddr2 Sdram Images and Descriptions
In addition to still images, many of Amazon’s Ddr2 Sdram have videos. This makes it easier for you to see exactly what you are purchasing. Amazon’s Ddr2 Sdram descriptions are also quite good. In many cases, Amazon repeats the descriptions furnished by the manufacturer. In other cases, they write their own.
(5) The Amazon Site is Easy to Navigate
Ddr2 Slot Colorado
Navigating the Amazon site is easy. Even though the site is huge, you will not feel overwhelmed when searching for Ddr2 Sdram. This is partly due to Amazon’s filtering process. You can search for items by brand, price or user rating. You can also search for specific features.
How to Choose the Best Ddr2 Sdram (with Price and Reviews)
Although most Ddr2 Sdram are similar, there are several differences worth noting. Here are nine criteria to consider when choosing an Ddr2 Sdram:
Ddr2 Slot Colorado Springs
(1) Ddr2 Sdram Price and Reviews
Although price is not the only factor to consider, it is nevertheless extremely important. The price of an Ddr2 Sdram should be in line with its value. You can compare Ddr2 Sdram reviews to make sure you are getting a fair price. This is easy to do on Amazon.
(2) Demand
The demand for a particular Ddr2 Sdram is a good indication of its ability to perform the functions for which it was designed. If a product has been around for a while and still has a high demand, it is likely a good product.
(3) Material
Ddr2 Sdram materials differ from manufacturer to manufacturer. Consider where and how you will be using your Ddr2 Sdram to determine if one material would be better than another.
(4) Size
Like most products, Ddr2 Sdrams come in various sizes. Do you need a large Ddr2 Sdramor a small one? Think about where you will use your Ddr2 Sdram in order to determine the best size. You can also read the customer reviews on Amazon to see what others are saying about the size of the unit they purchased.
(5) Color
Ddr2 Sdrams also come in a variety of colors. Do you need a particular color? You should also consider whether the color of your Ddr2 Sdram would have any effect on the efficiency of its operation.
(6) Durability
The durability of an Ddr2 Sdram will be contingent on the materials used as well as the quality of the manufacturing process. Additionally, the type of Ddr2 Sdram you purchase may affect its durability.
(7) Storage
Will you need to store your Ddr2 Sdram? If so, you should consider the size and weight of the Ddr2 Sdramto make sure that it can be stored properly. Also, give some consideration to the type of climate in which your Ddr2 Sdram will be stored.
(8) Customer Ratings
Customer rating is one of the best criteria for choosing an Ddr2 Sdram. It is hard to know exactly how an Ddr2 Sdram will perform until you get it home and try it out.
(9) Warranty
Make sure the Ddr2 Sdram you are considering is backed by a good manufacturer’s warranty. If it isn’t, you might be better off with another ones.