RAM is a computer’s high-speed short-term storage. It processes information significantly faster than data stored on a hard drive.
It allows you to quickly execute tasks like typing a sentence, saving a file, or jumping into a video game. Without it, your computer would slow down to a crawl or crash.
Memory Types
There are different types of RAM available in the market. They differ in shape, size and speed. Understanding the differences between them is important when you’re upgrading or building a computer. If you get the wrong type of RAM, your system might not work.
A static random access memory (SRAM) uses six transistors in each memory cell, allowing it to transfer data more quickly than dynamic random access memory (DRAM). It is expensive and only found in high-speed cache for the CPU, and is not user-replaceable.
DRAM uses transistors and capacitors to store data, and can transfer data on both the rising and falling edges of a clock signal. It’s most commonly used in PCs as primary memory, and is also known as main memory.
The amount of RAM in a computer is usually specified by the motherboard. Memory modules come in a range of sizes and speed, and have different ‘brands’ such as DDR.
Memory Capacity
The amount of RAM your computer has impacts how many programs you can run simultaneously. The more RAM you have, the faster your system will run.
RAM stores temporary data while your computer is running, and it disappears when the power is turned off. That makes it different from a hard disk drive or SSD (solid-state drive), which acts as long term storage.
Depending on your computer usage, you may need more or less RAM. Upgrading to a larger capacity will give your computer more room for running memory-hungry programs, such as gaming, photo and video editing, virtualization, and 3D modeling.
Look for RAM that has a high speed rating, measured in megatransfers per second or gigahertz (GHz). Faster RAM allows data to be read and written more quickly, which improves performance. It’s also important to choose a RAM that is compatible with your motherboard and processor. Using the wrong type of RAM can cause your system to overheat or perform poorly.
Memory Speed
RAM processes data from twenty to one hundred times faster than storage devices, such as a hard drive or solid-state drive. Whenever you open an application or file on your computer, the operating system retrieves it from its long-term storage in the HDD/SSD and replicates it into RAM for immediate access.
As technology advances, manufacturers develop memory modules with greater speed and density. When choosing a new module, look for the manufacturer’s specification of their product. For example, you might see “CL” (Column Address Strobe Latency) listed on the product flyer or in a spec sheet for a particular RAM type.
These numbers refer to the number of memory clock cycles it takes for a command to be processed by the processor and the data to be stored or retrieved from the memory chip. Increasing the clock speed of your computer’s RAM increases its overall performance. However, it’s important to note that memory performance also depends on the CPU’s clock speed.
Memory Latency
The ability to perform processing tasks without waiting for data is an important factor in performance. If processors have to wait for data to come from storage it will take longer to complete an operation compared to an operation that reads directly from memory.
The CAS latency is a measure of how long it takes for RAM to output the data requested by the CPU. It takes into account how many RAM clock cycles it takes to execute the command and output the data, which is why the lower number the better.
While RAM frequency has a bigger impact on performance than latency, it isn’t a good idea to ignore the latter. You should look for a kit that has low CAS latency and pay attention to the duration of each cycle when comparing kits. Also, remember that it’s less expensive to access data in a row-based pattern by thread than in a column-based pattern.