Difference Between ECC and Non-ECC RAM

As everyone knows, Error correction code memory (ECC memory) is a type of computer data storage technique. It identifies and fixes the most common errors which could otherwise lead to data corruption or system crashes. In other words, it is one of the most important tech for this loss and system errors prevention. There will be people who have such a question: now the memory technology is improved greatly, do we still need ecc memory? This note will help you find clue out step by step.

1 What Causes Errors in RAM?

The ram error is caused by electromagnetic interference inside the computer. This interference will cause the units of DRAM (Dynamic Random Access Memory) to spontaneously change to the opposite state. Unit errors may be hidden, that is, they will not have a serious impact on the data.

However, the memory units are interrelated, so unit changes may affect the entire operational system, resulting in system errors, especially when strict operation is required. To be specific, memory errors will cause security vulnerabilities, crashes, transcription errors, lost transactions, and corrupted or lost data, and one of the most common type of memory error is a single-bit error.

2 Is ECC RAM Better?

In the face of these problems, if memory can fix the error itself, what will it look like? That is ECC RAM.

Memory Chips Difference

ECC RAM is server memory. This type of memory module has an ECC error check storage chip (the number of storage chips is an odd number). The application of ECC can ensure that the server is safer and more stable during operation. However, the number of chips stored in ordinary memory sticks is even. In reality, ECC RAM has 9 memory chips instead of 8.

Error Checking and Correcting

The ECC memory is equipped with ECC error checking technology. After error checking and correction, the stability and reliability of the server system can be effectively guaranteed. For ordinary ram, when the word detects an error, the error location cannot be determined, and the error cannot be corrected. Therefore, for a single task that takes a long time and cannot be suspended or error, ECC memory is an inevitable choice. However, ordinary PCs will not use it because of high cost price.

Application Difference

Because ECC memory can effectively store and maintain data integrity, and is equipped with check and correction technology, ECC memory further reduces data corruption. Therefore, it is mostly used in servers and graphics workstations such as financial and scientific industries. Non-ECC memory sticks are more suitable for the general public use.

Capacitor Difference

As server memory applications require higher capacity, ECC memory modules usually start at 4GB, while ordinary memory modules usually start at 2GB. The standard configuration on home computers is 4~8GB of memory.

Price Difference

Due to the higher tech of ECC memory sticks, and its capacity is also larger than ordinary memory. Therefore, ECC memory sticks are more expensive than ordinary memory.

Difference between ECC RAM and Non-ECC RAM

^ ECC RAM

• Auto detects memory errors and corrects it
• More expensive
• 2% disadvantage of performance
• Recommended for system with high-value data (Servers and workstations)

^ Non-ECC RAM

• Not capable correcting errors but some are capable of detection
• Less expensive
• 2% advantage of performance
• Recommended for standard use (Home system)

3 Server Memory: ECC RAM or Non-ECC Memory?

ECC memory is usually used in servers or graphics workstations. Because of the check and correction function, when there are some read and write errors in the memory, the ECC RAM can correct these errors and reduce the probability of downtime/blue screen. Guaranteed data storage and accuracy of reading and writing.

Server memory and ordinary PC memory are very similar, there is no obvious difference in appearance and structure, but its price is higher than ordinary memory. There are three main types of server memory: SDRAM, DDR, and DDR2. At present, server memory is mostly used DDR and DDR2. With the time goes by, server uses some new technologies now, such as ecc, chipkill, register, hot swap technology, and FB-DIMM (full buffer memory module) etc.

More server memory currently adopts ECC and REG ECC technologies. The chips on REG ECC memory are generally 2-3 more than ordinary motherboards, mainly PLL (phase locked loop) and Register IC. ECC and ECC REG memory have been developed for a period, and the frequency mainly has 133, 266, 333, 400, 533, 667 stages.

What is RECC?

The specific uses of RECC memory are as follows: phase locked loop chip, the bottom of the memory stick are smaller than Register ICs. Generally, there is only one, which can adjust the clock signal and ensure the signal synchronization between the memory modules. The smaller IC chip (2-3 pieces) at the bottom plays a role in improving the driving capability. Server products need to support large-capacity memory. The motherboard alone cannot drive such a large-capacity memory.

Instead, the memory module with Register is used to improve the driving ability, so that the server can support up to 32GB of memory. Because of the PLL and Register chips, the server memory capacitor can be made very large, it can better meet the endless requirements of the ever-increasing software for memory. Therefore, it is recommended that the server whose requirement over 16G use RECC RAM.

RECC has one more register. We can understand the function of the memory as a book directory. When the memory receives a read and write command, it will retrieve this directory first, and then perform read and write operations, which will greatly improve the efficiency of the server memory. So some people mistakenly think that RECC RAM runs slower than ECC RAM. The Register memory that can be used at present also has ECC function, and some motherboards require the memory to support Register. In fact, all registered memory is ECC memory.

The use of ECC memory requires the support of other computer components, such as the motherboard and cpu, and may also need to be set in the BIOS before it can be used on most server CPUs and motherboards (some non-server CPUs and motherboards also support). In addition, when purchasing ecc memory, you need to pay attention to whether it is ecc udimm or ecc rdimm or ecc lrdimm or ecc 3ds rdimm or something else. Because your computer configuration may not support some types.

What’s more, all of the modern, contemporary storage drives use ECC at some level internally. HDD, SSDs. The data densities of the HDD push the edge where need to keep up with track integrity. NAND in SSDs tend to loose data bits in usage over time. The SSD controller in the T2 isn't remarkable on the ECC dimension. All the ones that store the data encrypted 'at rest' basically have to if going to be competently implemented. In addition, ECC generally works on all Ryzen Chips minus the APUs (with the exception of the pro apus), they tend to not be on the QVL since it costs time and money to do that.

Previously published at What is the Benefit of ECC Memory?