512MB MSI Microstar EX401 RAM memory

Start by determining how many megabytes (MB) your printer / notebook/ computer can hold.
The BEST Electronics Memory selector tool shows you the maximum memory, that your system can hold. You will find the maximum memory your system can support in the system description.
 

Determine how many memory modules you can install.

The number of total memory slots in your system you will find in the field: "Memory Expansion"
The first number refers to the total number of slots your system has for memory modules. For example, if the first number is "2," a maximum of two modules can be installed. The numbers in parentheses refer to the number of banks in your system. If you have banks of 1, you can purchase and install one module at a time. If you have banks of 2, you need to purchase and install two modules at a time, and if you have banks of 4, you need to purchase and install four modules at a time.

How many modules are in your system now? Now that you know how many memory slots your computer has, determine how many modules are currently installed in your computer. You can see it: open your computer's case, identify the memory slots and then count the number of empty slots.

Putting it all together.
Based on the number of memory slots and the number of megabytes your computer can hold, determine which of the compatible upgrades will best meet your computing needs and budget.

Let's say you've taken our advice, and you've decided you want your computer to have a maximum of memory.

Example:
Refer to Step 1 and make sure your system can support at least 512MB of memory. If the maximum amount of memory your computer can support is less than 512MB, use the maximum number as your goal.

Subtract the amount of memory currently installed in your computer (Step 2) from 512MB (or your maximum memory). This will tell you how many megabytes you need to add to reach 512MB total memory.

Taking into consideration the number of empty memory slots in your computer, choose a module (or modules) from the compatible memory upgrades listed at the top of this page that will get you to 512MB total memory.

For printers we recommend to choose the maximum of possible memory. Notebooks and pc´s with Windows XP require at least 256 MB.