As with any type of product, memory can vary in the quality from one manufacturer to another. In general, the larger, more established brand name companies are more consistent in adhering to tight design specifications, using high-quality components, and establishing certified quality control processes for manufacturing and thorough testing. That's not to say that lower-quality modules don't work fine - they may be the right solution, depending on how hard you work your system. In deciding the level of quality you require, consider the following:
- If the memory you buy doesn't perform well, will you be comfortable returning it for a replacement? Would you have the time to deal with removing the memory and waiting a couple of days to a week to get the situation resolved?
- When memory is of low quality, you often experience intermittent problems, such as the computer "freezing" unexpectedly, or having frequent errors. How often do you save your work, and if you were to lose your work, how much would that cost you? If you use your computer to play games, read email, and surf the Internet, such interruptions and losses may not be a big problem. But if you're running a business, losing a few hours of work could be a serious matter.
- The biggest risk with unreliable memory is data corruption: that is, some bits of data may change or be read incorrectly. The result of data corruption could be as harmless as a syntax error in a document, or as potentially serious as a miscalculation in a spreadsheet. How important is the accuracy of the work you do on your computer? Again, if you use your computer for gaming, writing letters, and the Internet, it may not be a problem. But if you're managing your finances, you may want to do all you can to assure the reliability of your data.
- Just like all products, the quality and durability you require depends on how you use it. Computer applications that require a lot of memory usually work the memory very hard. These applications often work better with memory that exceeds the system's speed and reliability specifications. If you're working in multimedia or using heavy number-crunching programs, the chance of a lower-quality memory module failing is greater than if you're only doing light work, such as simple word processing.
ASSESSING MEMORY QUALITYHere are some important factors to keep in mind when assessing the quality of a brand of memory:
Designers of memory modules can follow strict specifications or take short cuts to save money on components. In general, manufacturers who do in-house design have more control over the quality of the module than those who farm this work out.
The quality of the DRAM chips, PC boards, and other components used on the module are critical to the overall quality of the module. Premium memory chips can cost up to 30% more than low-grade chips and high-quality PC boards cost about 50% more than lower quality alternatives.
Many factors in module assembly can affect the overall quality of the module. In addition to proper handling of components, solder quality affects how reliably information can travel from the chip to the module and back. The temperature and humidity in the assembly and storage areas must be regulated to prevent warping, expansion, and contraction of components during assembly.
Electro-Static Discharge (ESD) is one of the most common causes of damage to a memory module. ESD damage can result from excessive and inappropriate handling. Memory modules should only be handled by workers who are properly "grounded" and modules should be properly packaged to protect against ESD during shipping.
The more thoroughly memory has been tested before it is shipped, the less chance of problems during operation. In addition to standard production tests to ensure that the modules have been built correctly, memory can be tested for compatibility in the systems in which it will be used. The DRAM core can be tested for chip reliability, and modules can be tested "at speed" to make sure they will work in high-use situations. Some companies perform testing at all levels, and some do less testing.