OCZ PC2-5400 (DDR2-667) Memory (RAM)

What You Need to Know about OCZ DDR2-667 PC2-5400 RAM

DDR2, which stands for double data rate, is a type of memory module produced by OCZ. Whereas previous types of memory could transmit data only once or twice per clock cycle, DDR2 can transmit data four times per clock cycle. You can use DDR2-667 to increase the amount of programs and files you can have open on your computer at a single time.

DDR2-667 and PC2-5400 are two ways of describing the same type of product. DDR2-667 describes the total number of transfers completed per second. In other words, the number of times data is transferred, not the total amount of data. In this case, it would be 667.67 million transfers per second. PC2-5400 describes the peak bandwidth rate. In other words, the maximum amount of data transferred per second.

The bandwidth is calculated by multiplying the number of transfer by eight. This would be 5,333.33 megabytes per second. This is the maximum theoretical limit, and real-world performance may be lower. Another way of measuring DDR2 is by its latency. The latency is the slight delay that occurs when the memory performs certain actions. This is measured in the number of clock cycles. There are two types, named DDR2-667C and DDR-667D, which have different latencies. The former has a lower latency than the latter.

Yes, but it has to be specifically designed for error identification and correction. If the module can correct errors, it will be identified as ECC, or error-correcting code. This is commonly used for certain professional or scientific tasks which require a high degree of fidelity from the data. Otherwise, if it is not error-correcting, then it will be labeled as non-ECC.

There are several factors that affect compatibility between DDR2 and your motherboard, including:

• DDR technology: Some motherboards will only accept certain types of DDR2 but not others. Check your motherboard to make sure it is compatible. In addition, if you are combining multiple RAM together, they will both need to be from the same generation of DDR technology.
• Number of pins: There are two types of modules: DIMMs and SO-DIMMs. DDR2 DIMMs, which are designed for desktop computers, have 240 pins. DDR2 SO-DIMMs, which are designed for laptop computers, have 200 pins. This determines how the RAM fits into the motherboard.
• Buffered or registered memory: Buffered RAM adds an additional register between the RAM and CPU. The register buffers, or temporarily stores, the data before it's sent to the CPU. This reduces electrical load on the controller at the expense of a slight delay to the signal. It is primarily suited for computer systems with a lot of additional memory. The extra buffered signal helps to keep the entire system stable. A standard buffer is compatible with most types of motherboards. Fully buffered memory, however, is only compatible with specialized motherboards.