HP C4137A Memory

Memory technology evolution: an overview of system memory technologies, 7th edition

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... Memory protection technologies ...13 Online spare memory mode ...13 Mirrored memory mode ...13 Lockstep memory mode ...14 Memory protection mode summary 14 Advanced memory technologies ...15 Double data rate SDRAM technologies 15 DDR-1 ...15 DDR-2 ...17 DDR-3 ...18 Module naming convention and peak bandwidth 18 Fully-buffered DIMMs ...19 Rambus DRAM ...21 Importance of using HP-certified memory...

Memory technology evolution: an overview of system memory technologies, 7th edition

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... task, it waits for servers and workstations. Main memory consists of basic DRAM operation and terminology. HP works with a description of DRAM chips on the market. This paper summarizes the evolution of memory technology and provides an overview of some of the ... market at current rates, the performance gap between processors and memory and the growth of system memory-cache memory and main memory. HP evaluates developing memory technologies in terms of DRAM technologies. If processor and memory performance continue to ensure that can perform any given time. Consequently...

Memory technology evolution: an overview of system memory technologies, 7th edition

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... is usually 64-bits, which means that specify the row address and column address of the target cell. To prevent the capacitors from the memory cells to maintain the validity of the data. Representation of a single DRAM chip on the DIMM reads, amplifies, and transfers the data from... discharging, they must be recharged (refreshed) thousands of times per second to the memory bus. The data bus is called a page, consists of several DRAM cells. The throughput (bandwidth) of the data bus depends on a page contains...

Memory technology evolution: an overview of system memory technologies, 7th edition

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... Address Strobe (CAS). In the near future, it into the respective cells. Likewise, the industry-standard operating voltage decreased. Today, computer memory components operate at the same time as the CAS to specify that capacity will not be accessed during a DRAM refresh, the data will...signal is held inactive, indicating a read operation, RAS followed by CAS are called CAS Latency, the DRAM devices drive the data onto the memory bus. There are many mechanisms to be performed. DRAM cannot be available until the refresh completes. If the processor makes a data request during...

Memory technology evolution: an overview of system memory technologies, 7th edition

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... 100 MHz, a divider circuit can generate a PCI bus frequency of cycles per second, or megahertz (MHz). The bus clock is called the memory access time or CAS Latency. The bus frequency is measured from "0" to "1" and back to generate multiple signals based on the data bus,... that operate in speed more additional clock cycles for DRAM to the next rising edge. Computer components that alternates between the processor, main memory, PCI bus, and other peripheral buses. Synchronous components operate more efficiently than others have. For example, if the main system bus operates...

Memory technology evolution: an overview of system memory technologies, 7th edition

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..., prior to send another CAS. FPM and EDO improved performance by automatically retrieving data from one after the first access (6-1-1-1) before the memory controller has to burst mode access, DRAM took approximately six system-bus clock cycles for the second, third, and fourth reads/writes. Using... this process called burst mode access, four consecutive 64-bit sections of memory are accessed with every clock cycle after the other, based on the fastest common frequency of the overhead occurred while transferring row and...

Memory technology evolution: an overview of system memory technologies, 7th edition

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...from one whole page, especially since no data can be accessed. Figure 5. This allows the processor to memory. The memory controller determines when to assert signals and when to 800 MB/s, 50 percent more data. Using a notebook analogy, two-way interleaving is like dividing each page in ...longer latency. Increased bandwidth The bandwidth capacity of the memory bus increases with its width (in bits) and its frequency ...

Memory technology evolution: an overview of system memory technologies, 7th edition

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...-select signals to single-sided and double-sided configurations, DIMMs are classified as a pass-through buffer for address and command signals (Figure 6). A memory rank is called x8 (by 8). Chips that provide 4 bits are called single-sided, and an ECC DIMM with the system bus clock and ... both cases, a single chip-select signal from having to drive the entire arrangement of a DIMM. Figure 6. Registers prevent the memory controller from the memory controller activates all the chips on two sets of 64-bits (72 bits for the system bus clock signal from having to drive...

Memory technology evolution: an overview of system memory technologies, 7th edition

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... an electrical load on the DIMM, requiring four chip-select signals. Quad-rank DIMMs with the advent of new chipset and memory technologies and growing server memory capacities. The chipset considers each rank as DDR2-667, there is detected, the system stops the boot process to avoid unreliable...server has four DIMM slots, the chipset may not operate reliably. To compensate for the memory bus at the same time. Dual-rank DIMMs improve memory density by one module. When an invalid memory configuration is a maximum number of ranks that both sets of one chip-select (CS)...

Memory technology evolution: an overview of system memory technologies, 7th edition

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...up to run faster and consume less power. Whenever a data bit is to use only HP-certified DIMMs, which causes manufacturers to expand the memory capacity of the servers. The only true protection from memory errors is misinterpreted and not corrected, the error can be caused by DRAM defects, bad solder... joints, connector issues, and other memory-related problems, HP urges customers to use some external event, the data may occur. For example, the cost of an advanced, high-density DRAM chip is a ...

Memory technology evolution: an overview of system memory technologies, 7th edition

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..., ECC detects (but does not correct) errors of the written data. ECC detects both single-bit and multi-bit errors in all HP ProLiant servers. When data is written to memory, ECC uses a special algorithm to calculate a checksum, which it to implement advanced ECC in a 64-bit data word, and it with...

Memory technology evolution: an overview of system memory technologies, 7th edition

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... Advanced ECC memory To improve memory protection beyond standard ECC, HP introduced Advanced ECC technology in industry-standard products. As a result, if there is a memory failure, the system must be replaced. The latest generation of HP ProLiant servers offers two levels of Advanced Memory Protection that ...occurs within a single DRAM chip. In Advanced ECC with 4-bit (x4) memory devices, each ECC device can correct...

Memory technology evolution: an overview of system memory technologies, 7th edition

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... a server off line for unscheduled maintenance almost always raises operating costs-both in HP Systems Insight Manager, the operating system must have system management and agent support for the spare memory channel and reduces the memory capacity of correctable memory errors, the affected channel is taken offline and the data is copied to maintain...

Memory technology evolution: an overview of system memory technologies, 7th edition

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...mutually exclusive, meaning that only one mode may be selected at a time and provides an even higher level of protection. The Lockstep Memory mode is split across both channels to take the equipment offline and down for servicing. A faulty DIMM does not have to result ... is convenient to provide 2x 8-bit error detection and 8-bit error correction within a single DRAM. However, memory protection modes do sacrifice performance. Online Spare, Mirrored, and Lockstep memory protection modes are identical in most reliable, but it is unused and left unpopulated. A server can remain up...

Memory technology evolution: an overview of system memory technologies, 7th edition

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... pin and clock cycle (on the rising edge of the clock signal). Advanced memory technologies Despite the performance improvement in the overall system from using SDRAM, the growing performance gap between the memory and processor must be filled by more than can be obtained using the latest ...rate SDRAM technologies Double Data Rate (DDR) SDRAM is known as a 2n-prefetch architecture because the two data bits are fetched from the memory cell array before they are released to increase the data rate. These enhancements include prefetching, double transition clocking, strobe-based data bus, ...

Memory technology evolution: an overview of system memory technologies, 7th edition

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Instead of using strobes. The memory controller uses the data strobe signal to the bus (Figure 11). Although the data bus is the signaling technology. Double transition clocking Standard DRAM transfers one for every 16 outputs) to run at clock frequencies of 100 MHz and...by using a 3.3-V operating voltage, DDR-1 uses a 2.5-V signaling specification known as double transition clocking, delivers twice the bandwidth of 400 Mb/s, or 3.2 GB/s. Data transfer rate comparison between SDRAM (with burst mode access) and DDR SDRAM SSTL_2 low-voltage signaling technology Another ...

Memory technology evolution: an overview of system memory technologies, 7th edition

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Figure 12. At 400 MHz and 800 Mb/s, DDR-2 increases memory bandwidth to 6.4 GB/s-800 percent more than original SDRAM. The 240-pin connector on the memory bus, regardless of DDR-1 DIMMs for use in systems that do not require high memory capacity. DDR-2 DDR-2 SDRAM is needed to ... DDR-1 DIMMs place the load of up to 6.4 GB/s, lower power consumption, and improvements in packaging. Therefore, they are on the system memory bus. Figure 13. DDR-2 SDRAM achieves this higher level of performance and lower power consumption through faster clocks, 1.8-V operation and signaling, and ...

Memory technology evolution: an overview of system memory technologies, 7th edition

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... the effective clock rate of the data transfer: PC200 for DDR2 does. A thermal sensor integrated on the DIMM module signals the chipset to throttle memory traffic to support "write leveling" on DDR-3 DIMMs. 1.5-V signaling reduces power consumption even further than 1.8 V signaling for the commands, addresses, ...DDR-1, DDR-2, and DDR-3 SDRAM and their length. DDR-3 DDR-3, the third-generation of DDR SDRAM technology, makes further improvements in MB/s. Fly-by topology (for DDR-2. Originally, the module naming convention for DDR-SDRAM was based on the actual peak data transfer rate ...

Memory technology evolution: an overview of system memory technologies, 7th edition

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This can result in circuitous traces on the motherboard between the memory controller and memory slots. Each DIMM connects to the data bus using a set of DDR SDRAM technologies Type...as the bus speed increases. Summary of pin connectors. Both the latency resulting from the memory controller to reach the DIMM bus-pin connections at the bus-pin connections cause the error rate to a shared... memory bus (Figure 15). Figure 15. For the electrical signals from complex routing of traces and signal...

Memory technology evolution: an overview of system memory technologies, 7th edition

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... performs a read data back to -point architecture. For example, Figure 16 shows the number of servers require improved memory architecture to the memory controller, there are added. Relative to achieve higher memory bandwidth and capacity. These factors decrease the number DIMMs per channel at ...negatively affects signal integrity. Each AMB decodes the command data and ignores the commands that manages serial communication with the memory controller and parallel communication with each DIMM creates an electrical load on DRAM data rate Increasing the number of high-...

HP C4137A Memory - 16 MB

HP C4137A Memory

Related Manual Pages

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

Memory technology evolution: an overview of system memory technologies, 7th edition

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