We can usually see the model number and parameters on the label of a memory module (SDRAM). The model number is defined by the memory manufacturer itself, and the definition rules vary among different manufacturers. Generally, the memory parameters can be identified through the model number. At the same time, the parameters are also marked on the memory label, and the definition of the parameters basically follows the industry standard, which can intuitively identify the performance of the memory. Some manufacturers do not print the parameters on the memory, which brings some difficulties to the identification of memory performance. This article mainly explains the identification of memory parameters.

The normal representation method follows the format: "Capacity Number of Memory Chips Generation - Rate (Identification) Latency Voltage", such as 4GB 2Rx8 PC3-1200S-11-11-E3.

Memory Capacity

The larger the number, the larger the temporary storage, and common ones include 16GB, 8GB, 1GB, 512MB, 256MB, etc.

Number of Memory Chips

The number of memory chips represents the number and welding surface of the memory chips, with the format of aRxb, such as 2Rx8. 1R represents that there are memory chips on only one side, and 2R represents that there are memory chips on both sides; x8 represents the number of memory chips per side. 2Rx8 represents that there are 8 memory chips on one side, totaling 16.

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Memory Generation

So far, the common memory on the market is DDR memory, with a total of five generations. The representation is PC1, PC2, PC3, PC4, PC5. The memory between different generations is not compatible and cannot be used together. Anti-idiot treatment has been made at the gold finger connector, and the position of the anti-idiot mouth at the gold finger is different for different generations.

If there is an L at the end, it represents the low-voltage version, such as PC3L.Design of Anti-Idiot Mouth

Memory Rate

12800 = 1600 x 8, the memory data transfer rate is 1600MHz.

PC2-12800 is also known as DDR2-1600.

Memory Label

Sometimes there may be letters following the memory frequency, such as 5300F.

U represents UDIMM memory

R represents RDIMM memory

P represents RDIMM's ECC memory

E represents ECC memory, Error Checking and Correcting technology, the full name is Error Checking and Correcting. It requires the motherboard to support, used for server computers.F, FB represents Fully Buffered ECC memory, which is incompatible with non-F memory, and the anti-misplacement port positions are inconsistent. It is used for server computers.

S represents SO-DIMM.

RDIMM: Full name (Registered DIMM), registered memory module, mainly used in servers, to increase memory capacity and stability, there are two types with ECC and without ECC, but the market is almost all ECC.

UDIMM: Full name (Unbuffered DIMM), unbuffered memory module, this is the standard desktop computer DIMM we usually use, there are two types with ECC and without ECC, generally without ECC.

SO-DIMM: Full name (Small Outline DIMM), small outline DIMM, the DIMM used in notebook computers, there are two types with ECC and without ECC.

Mini-DIMM: A new type of module that appeared in the DDR2 era, it is a reduced version of the Registered DIMM, used in high-end fields such as blade servers that have strict requirements for volume.

LatencyThe 4-4-4-8 represents the four parameters of latency, which are CL-tRCD-tRP-tRAS-CMD. The smaller the data, the smaller the latency time.

CL stands for timing, with CL9 indicating a timing value of 9.

Voltage

For example, 1.35V is a voltage value.