Laptop Memory Buyer's Guide

Selecting the Proper Type and Amount of RAM for a Laptop PC

Laptop Memory Modules
Laptop Memory Modules. ©Crucial

Certainly the more memory in a laptop the better but there are other concerns regarding memory. Laptops are generally more restricted in the amount of memory that can be installed in them. Sometimes access to that memory can also be a problem if you plan a future upgrade. In fact, many systems now will only come with a fixed amount of memory which cannot be upgraded at all.

How Much is Enough?

The rule of thumb that I use for all computer systems for determining if it has enough memory is to look at the requirements of the software you intend to run.

Check each of the applications and the OS that you intend to run and look at both the minimum and recommended requirements. Typically you want to have more RAM than the highest minimum and ideally at least as much as the highest listed recommended requirement. The following chart provides a general idea of how a system will run with various amounts of memory:

  • Minimum: 4GB
  • Optimal: 8GB
  • Best: >8GB

The ranges provided are a generalization based upon most common computing tasks. It is best to check the requirements of the intended software to make the final decisions. This is not accurate for all computer tasks because some operating systems use more memory than others. For instance, a Chromebook running Chrome OS runs smoothly on just 2GB of memory because it is highly optimized but can certainly benefit from having 4GB.

Many laptops also use integrated graphics controllers that use a portion of the general system RAM for the graphics.

This can reduce the amount of available system RAM from 64MB to 1GB depending upon the graphics controller. If the system is using an integrated graphics controller it is best to have at least 4GB of memory as it will reduce the impact of the graphics using system memory.

Types of Memory

Pretty much every new laptop on the market should use DDR3 memory now.

DDR4 has finally made it into some desktop systems but is still fairly uncommon. In addition to the type of memory installed in the laptop, the speed of the memory can also make a difference in the performance. When comparing laptops, be sure to check both of these pieces of information to determine how they may impact performance.

There are two ways that the memory speeds can be designated. The first is by the memory type and its clock rating, like DDR3 1333MHz. The other method is by listing the type along with the bandwidth. In the case the same DDR3 1333MHz memory would be listed as PC3-10600 memory. Below is a listing in order of fastest to slowest memory types for DDR3 and the upcoming DDR4 formats:

  • DDR4 3200 / PC4-25600
  • DDR4 2666 / PC4-21300
  • DDR4 2133 / PC4-17000
  • DDR3 1600 / PC3-12800
  • DDR3 1333 / PC3-10600
  • DDR3 1066 / PC3-8500
  • DDR3 800 / PC3-6400

It is fairly easy to determine the bandwidth or the clock speed if the memory is only listed by one value of the other. If you have the clock speed, simply multiple by 8. If you have the bandwidth, divide that value by 8. Just beware that sometimes the numbers are rounded so they will not always be equal.

Memory Restriction

Laptops generally have two slots available for memory modules compared to four or more in desktop systems.

This means that they are more limited in the amount of memory that can be installed. With current memory module technologies for DDR3, this restriction generally comes to 16GB of RAM in a laptop based on 8GB modules if the laptop can support them. 8GB is the more typical limit at this time. Some ultraportable systems are even fixed with one size of memory that cannot be changed at all. So what is important to know when you look at a laptop?

First find out what the maximum amount of memory is. This is generally listed by most of the manufacturers. This will let you know what upgrade potential the system has.

Next, determine how the memory configuration is when you buy the system. For example, a laptop that has 4GB of memory can be configured as either a single 4GB module or two 2GB modules. The single memory module allows for better upgrade potential because adding another module you are gaining more memory without sacrificing any current memory. Upgrading the two module situation with a 4GB upgrade would result in the loss of one 2GB module and a memory total of 6GB. The downside is that some systems may actually perform better when configured with two modules in dual-channel mode compared to using a single module but generally those modules need to be of the same capacity and speed rating.

Self-Install Possible?

Many laptops have a small door on the underside of the system with access to the memory module slots or the entire bottom cover may come off. If it does then it is possible to just purchase a memory upgrade and install it yourself without much trouble. A system without an external door or panel typically means that the memory cannot be upgraded at all as the systems is probably sealed. In some cases, the laptop may still be opened by an authorized technician with specialized tools so that it can be upgraded but that will mean a much higher expense to have the memory upgraded than just spending a bit more at the time of purchase to have more memory installed when it was built.

This is especially important if you are buying a laptop and intended to hold onto it for some time. If the memory cannot be upgraded after purchase, it is generally advisable to spend a bit more at the time of purchase to get it at least to as close to 8GB as possible to offset any potential future need. After all, if you then need 8GB but only have 4GB that can't be upgraded, you are hampering the performance of your laptop.