How to Test RAM Timing

RAM module

Nearly all computers have Random Access Memory (RAM). The different types of RAM are single in-line memory modules (SIMMs), dual in-line memory modules (DIMMs), SO-DIMM chips, SDRAM and DRAM chips and RIMM and SO-RIMM chips. You can use software to help identify and test the RAM timing on your motherboard. For example, a CPU-Z can gather information about RAM specifications and other main devices on your computer.

Things You'll Need

• Windows operating system
• RAM modules

Instructions

1. Browse the Internet and search for the latest version of CPU-Z. Find the icon for the software on your computer and click on it to run the setup executable file.

2. Select a folder and save the files. Follow the Windows on-screen instructions. The first time that you use CPU-Z, the utility installs a service. After the first run, you can use CPU-Z from any account without administrator privileges.

3. Click the icon to run CPU-Z. A pop-up window will appear on your display screen. Locate and press the “Memory” tab button. CPU-Z will display information about the RAM that is installed on your motherboard.

4. Write down the following information: “Type”, “Size”, “CAS# Latency (CL)”, “RAS# to CAS# Delay (tRCD)” and “RAS# Precharge (tRP).

5. Press the “SPD” tab button. The utility will display information about a particular stick of RAM. Newer DIMM-modules include a EPROM-chip that holds information about the module. The 8-pin chip works as a SPD (Serial Presence Detect) that stores information about the RAM type. This will allow your BIOS (Basic Input Output System) to help tune the system bus and timings for optimal RAM performance.

6. Gather and record the following information for each of the RAM modules that are installed on your motherboard. Write down the “Slot #,” “Module size,” “Maximum bandwidth” and “Manufacturer.”

7. Keep this information in a safe place and use it when you want to upgrade or add more RAM on your computer. If you plan to overclock your computer, purchase well-reviewed and reliable RAM. It may cost more than low-timing memory, which can make a significant difference in your computer's speed.

Tips & Warnings

• If you prefer to open your computer case, locate the RAM modules and examine the chips, which usually have markings on them. Look for the manufacturer's part number. The part number is the longest number that is on the chips. Write down this information and log on to the Internet. Visit the manufacturer's website and search for information about the part number to learn more about the RAM modules.

References

• “Mike Meyers' A+ Guide: PC Technician Lab Manual”; Michael Meyers, Dennis Haley; 2007

Resources

• CPUID: CPU-Z
• Hardware Secrets: Understanding RAM Timings
• PC Guide: Memory Speed, Access and Timing