Memory modules Apacer PC2-5300: acquaintance and testing
Evgenie Rudometov,
Victor Rudometov
authors@rudometov.com
For high-powered desktop computers company Apacer Technology Inc. Releases PC2-5300 units differing not only high high-speed parametres, but beautiful design
Modern computers concern extremely difficult arrangements. They consist of a large quantity of the electronic units banked in fulfilling various computer functions of a subsystem. By their consideration traditionally select processors with units of their surrounding, and also video subsystem, audio, drives etc. The dynamic storage which is for storage of programs and data for operation with them concerns the major subsystems also.
Presented to the first models of personal computers only several chips integrated into structure of motherboards and possessing in size, calculated in kilobytes, memory fast evolved. As a result of this evolution separate chips have given way to the memory modules, fulfilled in the form of the miniature cards which are hooked up to the motherboard by means of special plugs on the motherboard. But also these cards fast varied. So, for example, within several years the SIPP units which have received a wide circulation have been superseded by SIMM units, and they in turn have been substituted by several generations of DIMM units incompatible among themselves, differing a design. Not only various variants modular dizajnov, but also interfaces, and, of course, information capacity however varied.
Now in desktop computers dynamic storage DDR2 SDRAM units konstruktiva DIMM with 240 contact electrodes dominate. Units of the given standard are released by considerable number of the companies and calculated for the different size reaching already 4 Gbytes.
However production of such companies differs not only information capacity. The important features are also maximum clock rates and time responses (tajmingi, timing), closely linked to operation of units. In aggregate all specified parametres define productivity of a subsystem of dynamic storage, and through it and productivity of all system of the computer.
As one of manufacturers of memory modules it is possible to result company Apacer Technology Inc. (Further it is simple Apacer). The given company has been grounded in 1997 Acer Group and is one of its independent business units. Here it is necessary to remind, that structure Acer Group except the specified company includes also such known brands as AOPEN, Winstron, BenQ, etc. Dynamically developing, company Apacer is one of the largest manufacturers of units of replaceable memory, permanently showing tendency to reaching of excellence of production.
For high-powered desktop computer systems company Apacer offers DDR2 SDRAM units, capable to work on the high clock rates providing high values of a pass-band (Bandwidth) for buses of a subsystem of dynamic storage. The size of the given units is in a band of 256 Mb – 2 Gbytes. They are released in konstruktive DIMM, have 240 contact electrodes, and 1,8 Century are calculated for a supply voltage
Such one of variants of such units has been given by company Apacer for acquaintance and testing. Appearance of the given units in a static protective packaging and without it is presented accordingly in a Fig. 1 and a Fig. 2.
Fig. 1. Dynamic storage Apacer PC2-5300 units in a static protective packaging
Fig. 2. Units of dynamic storage Apacer PC2-5300 and their marking
According to marking each of the given units of dynamic storage possess size of 1 Gbytes. Other parametres are ciphered in UNB PC2-5300 CL5 characters. These letter abbreviations mean, that units are nebuferizovannymi (unbuffered), type DDR2 SDRAM and calculated for operation with a transmission frequency of data to 667 MHz. Thus to the upper value of frequency there corresponds signal CAS # (CL) = 5 to what the last characters of the specified string the markings designated as CL5 testify.
The specified units of dynamic storage are oriented to usage as a part of subsystems of dynamic storage of the high-powered desktop computer systems functioning at high clock rates. Operation of units in such subsystems is accompanied by a considerable heat release that leads to rise in temperature of chips of memory. Especially strongly it appears at maintenance of units in the conditions of compact system units in which it is difficult to provide sufficient cooling. For rise of stability of operation of the specified units designers have supplied with their double-side metal slices of original design. On a plan of creators they should fulfil functions of cooling heat sinks for memory chips with which they have the thermal contact electrode.
However, in spite of the fact that the design and yellow-golden colour of slices, certainly, raise attractiveness in the opinion of potential buyers, it is impossible to forget about a functionality of the given units.
Key parametres characterising high-speed properties of Apacer PC2-5300 units, it is possible to define in the course of testing.
Pattern of the system used in testing:
· Motherboard AsusP5AD2-Premium (chip set I925X, memory DDR2, the slot of video PCI Express x16, ports PATA and SATA, BIOS Vendor — American Megatrends Inc., BIOS Version — 1009.002),
· Processor IntelPentium 4 with clock rate of a kernel of 3,4 GHz (LGA 775, kernel Prescott, the bus of 800 MHz, processing technique Hyper-Threading),
· Dynamic storage DDR2, two units on 1 Gbyte Apacer PC2-5300, two channels,
· ATIRadeon X600XT Videoadapter on bus PCI Express x16,
· Disk drives on hard disks SeagateST3400832AS (Barracuda 7200.8, 400 Gbytes, 8 Mb of the cache memory, 7200 rpm, Serial ATA/150),
· the Operating system of Windows 2003 Server Enterprise Edition, Service Pack 1.
As the testing tool known program RightMark Memory Analyzer V3.65 (http://cpu.rightmark.org), incorporating analysis components on a low level dynamic storage DDR2 units has been selected.
In the course of the analysis the results presented more low have been received.
Key parametres of Apacer PC2-5300 units received as a result of decryption SPD, fulfilled by means of RightMark Memory Analyzer V3.65, are resulted in Table 1 (hereinafter in tables denotations and the abbreviations used in program RightMark Memory Analyzer V3.65) are saved.
Table 1. Key parametres SPD
Modlue Type: |
DDR2-667 (PC2-5300) |
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Module Size: |
1024 MB |
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Max Frequency: |
333,33 MHz |
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Data Width: |
64 bits |
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Banks: |
2 |
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Supported CAS #: |
3.0, 4.0, 5.0 |
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Correction: |
None |
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Manufacturer: |
Apacer Technology |
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Refresh Interval: |
7,813 us, Self-Refresh |
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CAS # Latency (tCL): |
15,0 ns (5,0) |
15,0 ns (4,0) |
15,0 ns (3,0) |
Cycle Time (tCK): |
3,00 ns (333,33 MHz) |
3,75 ns (266,67 MHz) |
5,00 ns (200,00 MHz) |
RAS # to CAS # Delay (tRCD): |
15,00 ns (5,00) |
15,00 ns (4,00) |
15,00 ns (3,00) |
Row Precharge (tRP): |
15,00 ns (5,00) |
15,00 ns (4,00) |
15,00 ns (3,00) |
Activate to Precharge (tRAS): |
45,00 ns (15,00) |
45,00 ns (12,00) |
45,00 ns (9,00) |
Row to Row Activate (tRRD): |
7,50 ns (2,50) |
7,50 ns (2,00) |
7,50 ns (1,50) |
Activate to Activate/AR (tRC): |
60,00 ns (20,00) |
60,00 ns (16,00) |
60,00 ns (12,00) |
Activate/AR to AR (tRFC): |
105,00 ns (35,00) |
105,00 ns (28,00) |
105,00 ns (21,00) |
Contents SPD concerning to tajmingam memories, look standardly for units of type DDR2-667. Apacer PC2-5300 units support three values of delay of signal CAS #: 5, 4 and 3.
To the first there corresponds the period of a clock signal of 3.0 nanoseconds. This value is equivalent to frequency of 333.3 MHz. It provides a transmission frequency of the given 667 MHz for memory of type DDR2 .
To the reduced value of delay CAS # (CL4) there corresponds the period of a clock signal of 3.75 nanoseconds, 266,7 MHz linked to frequency . It sets for a subsystem of memory data transfer with frequency of 533 MHz.
And at last, last delay factor CAS # (CL3) is linked to the period of a clock signal of 5.0 nanoseconds, i.e. Corresponds to a mode of data transfer with frequency of 400 MHz.
It is necessary to mark, that for a used pattern of test system, the functional mode of a subsystem of memory with a transmission frequency of the given 533 MHz is automatically installed . The fragment of a screenshot of a startup screen is resulted in a Fig. 3.
Fig. 3. Activation of the computer system used in testing
The information on parametres of a subsystem of dynamic storage in which structure Apacer PC2-5300 units used in mode PC2-4300 are used, is presented in Table 2.
Table 2. Key parametres of a subsystem of dynamic storage
Memory Type: |
DDR2 SDRAM |
Total Size: |
2048 MB |
Frequency: |
267,55 MHz |
Channels: |
Dual (Interleaved) |
Refresh Interval: |
7,800 us |
CAS # Latency (tCL): |
3,0 cycles |
RAS # to CAS # Delay (tRCD): |
4 cycles |
Row Precharge (tRP): |
4 cycles |
Activate to Precharge (tRAS): |
8 cycles |
The Fig. 4 representing a screenshot testifies to high-speed parametres of a subsystem of dynamic storage , received also by means of program RightMark Memory Analyzer V3.65. This screenshot shows results of testing in which result estimated values of a pass-band are received.
Fig. 4. Estimated values of a pass-band of a subsystem of memory
Estimating the resulted results of testing, it is necessary to mark, that in the selected pattern of hardware automatically installed functional mode of a subsystem of memory does not allow to realise potential of Apacer PC2-5300 units to the full. However motherboard AsusP5AD2-Premium allows to instal in a manual mode of customisation BIOS Setup for a subsystem of memory a mode of 600 MHz. This possibility also has been realised in one of stages of led testing.
In this mode, predictably, Apacer PC2-5300 units have shown a stable operation with productivity high level, that however, and it was expected from products of the given manufacturer.
In summary it is necessary to mark, that the potential put in pawn in Apacer PC2-5300 units to the full can be realised only at usage of processors with a transmission frequency of data on the system bus of 1066 MHz supported by appropriate motherboards. In such systems high-speed units provide optimal equation concerning generated streams of the information.
Unfortunately while similar processors and cards yet have not received a wide circulation. Nevertheless, already today PC2-5300 units are irreplaceable components of the systems constructed by enthusiasts, experimenting modes overclocking.
Considering that in modes with the reduced frequencies memory modules Apacer PC2-5300 show rather low delays, they can be recommended and for a wide range of the users who do not have while in the computer systems modern High End processors.
Memory modules Apacer PC2-5300 have been given by the European representation of company Apacer
Article is published in log the Computer the Price (Computer Price).