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RDIMM
Registered (also called buffered) memory modules have a register between the DRAM modules and the system's memory controller. They place less electrical load on the memory controller and allow single systems to remain stable with more memory modules than they would have otherwise. When compared with registered memory, conventional memory is usually referred to as unbuffered memory or unregistered memory. When manufactured as a dual in-line memory module (DIMM), a registered memory module is called an RDIMM, while unregistered memory is called UDIMM or simply DIMM. Registered memory is often more expensive because of the lower number of units sold and additional circuitry required, so it is usually found only in applications where the need for scalability and robustness outweighs the need for a low price for example, registered memory is usually used in servers. Although most registered memory modules also feature error-correcting code memory (ECC), it is also possible for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ECC Memory
Error correction code memory (ECC memory) is a type of computer data storage that uses an error correction code (ECC) to detect and correct n-bit data corruption which occurs in memory. ECC memory is used in most computers where data corruption cannot be tolerated, like industrial control applications, critical databases, and infrastructural memory caches. Typically, ECC memory maintains a memory system immune to single-bit errors: the data that is read from each word is always the same as the data that had been written to it, even if one of the bits actually stored has been flipped to the wrong state. Most non-ECC memory cannot detect errors, although some non-ECC memory with parity support allows detection but not correction. Description Error correction codes protect against undetected data corruption and are used in computers where such corruption is unacceptable, examples being scientific and financial computing applications, or in database and file servers. ECC can als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Error-correcting Code Memory
Error correction code memory (ECC memory) is a type of computer data storage that uses an error correction code (ECC) to detect and correct n-bit data corruption which occurs in memory. ECC memory is used in most computers where data corruption cannot be tolerated, like industrial control applications, critical databases, and infrastructural memory caches. Typically, ECC memory maintains a memory system immune to single-bit errors: the data that is read from each word is always the same as the data that had been written to it, even if one of the bits actually stored has been flipped to the wrong state. Most non-ECC memory cannot detect errors, although some non-ECC memory with parity support allows detection but not correction. Description Error correction codes protect against undetected data corruption and are used in computers where such corruption is unacceptable, examples being scientific and financial computing applications, or in database and file servers. ECC can als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fully Buffered DIMM
Fully Buffered DIMM (or FB-DIMM) is a memory technology that can be used to increase reliability and density of memory systems. Unlike the parallel bus architecture of traditional DRAMs, an FB-DIMM has a serial interface between the memory controller and the ''advanced memory buffer'' (AMB). Conventionally, data lines from the memory controller have to be connected to data lines in every DRAM module, i.e. via multidrop buses. As the memory width increases together with the access speed, the signal degrades at the interface between the bus and the device. This limits the speed and memory density, so FB-DIMMs take a different approach to solve the problem. 240-pin DDR2 FB-DIMMs are neither mechanically nor electrically compatible with conventional 240-pin DDR2 DIMMs. As a result, those two DIMM types are notched differently to prevent using the wrong one. As with nearly all RAM specifications, the FB-DIMM specification was published by JEDEC. Technology Fully buffered DIMM arc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dual In-line Memory Module
A DIMM () (Dual In-line Memory Module), commonly called a RAM stick, comprises a series of dynamic random-access memory integrated circuits. These memory modules are mounted on a printed circuit board and designed for use in personal computers, workstations, printers, and servers. They are the predominant method for adding memory into a computer system. The vast majority of DIMMs are standardized through JEDEC standards, although there are proprietary DIMMs. DIMMs come in a variety of speeds and sizes, but generally are one of two lengths - PC which are and laptop (SO-DIMM) which are about half the size at . History DIMMs (Dual In-line Memory Module) were a 1990s upgrade for SIMMs (Single In-line Memory Modules) as Intel P5-based Pentium processors began to gain market share. The Pentium had a 64-bit bus width, which would require SIMMs installed in matched pairs in order to populate the data bus. The processor would then access the two SIMMs in parallel. DIMMs were intr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SDRAM
Synchronous dynamic random-access memory (synchronous dynamic RAM or SDRAM) is any DRAM where the operation of its external pin interface is coordinated by an externally supplied clock signal. DRAM integrated circuits (ICs) produced from the early 1970s to early 1990s used an ''asynchronous'' interface, in which input control signals have a direct effect on internal functions only delayed by the trip across its semiconductor pathways. SDRAM has a ''synchronous'' interface, whereby changes on control inputs are recognised after a rising edge of its clock input. In SDRAM families standardized by JEDEC, the clock signal controls the stepping of an internal finite-state machine that responds to incoming commands. These commands can be pipelined to improve performance, with previously started operations completing while new commands are received. The memory is divided into several equally sized but independent sections called ''banks'', allowing the device to operate on a memory a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memory Latency
''Memory latency'' is the time (the latency) between initiating a request for a byte or word in memory until it is retrieved by a processor. If the data are not in the processor's cache, it takes longer to obtain them, as the processor will have to communicate with the external memory cells. Latency is therefore a fundamental measure of the speed of memory: the less the latency, the faster the reading operation. Latency should not be confused with memory bandwidth, which measures the throughput of memory. Latency can be expressed in clock cycles or in time measured in nanoseconds. Over time, memory latencies expressed in clock cycles have been fairly stable, but they have improved in time.Crucial Technology, "Speed ''vs.'' Latency: Why CAS latency isn't an accurate measure of memory performance/ref> See also * Burst mode (computing) * CAS latency * Multi-channel memory architecture * Interleaved memory * SDRAM burst ordering * SDRAM latency Memory timings or RAM timings descr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AnandTech
''AnandTech'' is an online computer hardware magazine owned by Future plc. It was founded in 1997 by then-14-year-old Anand Lal Shimpi, who served as CEO and editor-in-chief until August 30, 2014, with Ryan Smith replacing him as editor-in-chief. The web site is a source of hardware reviews for off-the-shelf components and exhaustive benchmarking, targeted towards computer building enthusiasts, but later expanded to cover mobile devices such as smartphones and tablets.For instance by: * * * * * Its investigative articles have been cited by other technology news sites like PC Magazine and The Inquirer. Some of their articles on mass-market products such as mobile phones are syndicated by CNNMoney. The large accompanying forum is recommended by some books for bargain hunting in the technology field. AnandTech was acquired by Purch on 17 December 2014. Purch was acquired by Future in 2018. History In its early stages, Matthew Witheiler served as co-owner and Senior Hardware ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitic Capacitance
Parasitic capacitance is an unavoidable and usually unwanted capacitance that exists between the parts of an electronic component or circuit simply because of their proximity to each other. When two electrical conductors at different voltages are close together, the electric field between them causes electric charge to be stored on them; this effect is capacitance. All practical circuit elements such as inductors, diodes, and transistors have internal capacitance, which can cause their behavior to depart from that of ideal circuit elements. Additionally, there is always non-zero capacitance between any two conductors; this can be significant with closely spaced conductors, such as wires or printed circuit board traces. The parasitic capacitance between the turns of an inductor or other wound component is often described as ''self-capacitance''. However, in electromagnetics, the term self-capacitance more correctly refers to a different phenomenon: the capacitance of a condu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Buffer
A digital buffer (or a voltage buffer) is an electronic circuit element used to isolate an input from an output. The buffer's output state mirrors the input state. The buffer's input impedance The input impedance of an electrical network is the measure of the opposition to current ( impedance), both static ( resistance) and dynamic ( reactance), into the load network that is ''external'' to the electrical source. The input admittance (the ... is high. It draws little current, to avoid disturbing the input circuit. Also called a unity gain buffer, a digital buffer does not intentionally amplify or attenuate the input signal. The digital buffer is important in data transmission, translating voltage pulses between connected systems. Buffers are used in registers (data storage device) and buses (data transferring device). A tri-state digital buffer can connect a device to a digital bus. The tri-state buffer's output is either high, low, or disconnected. Functionality A digital b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
20210402 Registered Versus Load-reduced DIMM Memory
1 (one, unit, unity) is a number representing a single or the only entity. 1 is also a numerical digit and represents a single unit (measurement), unit of counting or measurement. For example, a line segment of ''unit length'' is a line segment of length 1. In conventions of sign where zero is considered neither positive nor negative, 1 is the first and smallest Positive number, positive integer. It is also sometimes considered the first of the sequence (mathematics), infinite sequence of natural numbers, followed by 2, although by other definitions 1 is the second natural number, following 0. The fundamental mathematical property of 1 is to be a multiplicative identity, meaning that any number multiplied by 1 equals the same number. Most if not all properties of 1 can be deduced from this. In advanced mathematics, a multiplicative identity is often denoted 1, even if it is not a number. 1 is by convention not considered a prime number; this was not universally ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motherboard
A motherboard (also called mainboard, main circuit board, mb, mboard, backplane board, base board, system board, logic board (only in Apple computers) or mobo) is the main printed circuit board (PCB) in general-purpose computers and other expandable systems. It holds and allows communication between many of the crucial electronic components of a system, such as the central processing unit (CPU) and memory, and provides connectors for other peripherals. Unlike a backplane, a motherboard usually contains significant sub-systems, such as the central processor, the chipset's input/output and memory controllers, interface connectors, and other components integrated for general use. ''Motherboard'' means specifically a PCB with expansion capabilities. As the name suggests, this board is often referred to as the "mother" of all components attached to it, which often include peripherals, interface cards, and daughterboards: sound cards, video cards, network cards, host bus adapters, TV t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memory Bandwidth
Memory bandwidth is the rate at which data can be read from or stored into a semiconductor memory by a central processing unit, processor. Memory bandwidth is usually expressed in units of bytes per second, bytes/second, though this can vary for systems with natural data sizes that are not a multiple of the commonly used 8-bit bytes. Memory bandwidth that is advertised for a given memory or system is usually the maximum theoretical bandwidth. In practice the observed memory bandwidth will be less than (and is guaranteed not to exceed) the advertised bandwidth. A variety of computer benchmarks exist to measure sustained memory bandwidth using a variety of access patterns. These are intended to provide insight into the memory bandwidth that a system should sustain on various classes of real applications. Measurement conventions There are three different conventions for defining the quantity of data transferred in the numerator of "bytes/second": #The bcopy convention: counts the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
