The short and simple answer is yes! You CAN reuse old RAM sticks on a different PC IF AND ONLY IF the new computer also supports the same RAM type.
It is actually a fairly common practice to save your RAM sticks for use later on. Since RAM versions take a long time to update, it is a fairly common practice to reuse them on newer builds.
All motherboards have certain RAM compatibility requirements. Since motherboards are not backward and forward compatible with RAM versions, you have to make certain about what RAM sticks you have in hand before reusing them.
With the prices for chips and computer components sky-rocketing it is actually quite frugal to reuse older components whenever you can.
In the following article I will talk further about whether can you reuse old RAM sticks or not.
Before delving into whether you can reuse old RAM sticks or not, let us talk about the different RAM types:
Types of RAM: DDR, DDR2, DDR3, DDR4, DDR5
There are different RAM versions. With every newer version, the performance, its parameters and its profile changes.
Each different RAM type entails:
- A different physical profile – particularly the location of the notch for fitting the RAM sticks into the DIMM slot on the motherboard.
- A different voltage requirement
- A different RAM controller built into the motherboard’s chipset.
Given the three conditions above, RAM sticks are NOT compatible across generations. Meaning you CANNOT reuse a DDR3 RAM in a DDR4 motherboard and vice versa.
Also Read: Will DDR5 RAM Work on DDR4 Motherboard?
RAM Sticks Have Different Physical Profile
You can see the location of the notch/key on different RAM type differs. Hence, if you plan on reusing a RAM stick, make sure your motherboard is compatible with its particular version.
Read in Detail: How to Tell if RAM Will Work With Your Motherboard?
So Can You Reuse Old RAM Sticks?
Yes, you can reuse your old RAM sticks IF, both the motherboard and the old RAM stick is of the same type (Version).
In other words:
- A DDR4 RAM Stick CAN ONLY be reused with a motherboard that supports DDR4 RAM
- A DDR5 RAM Stick CAN ONLY be reused with a motherboard that supports DDR5 RAM
So on and so forth.
There is no adapter that can allow you to reuse an older RAM with a motherboard built for a newer RAM generation i.e DDR3 RAM stick on a DDR4 motherboard.
This Applies to Laptops Too
The idea that the RAM stick type has to be compatible with the motherboard isn’t just true for desktops. It also applies to laptop RAM sticks too.
A laptop’s SO-DIMM DDR4 RAM can ONLY work with another laptop that supports the same DDR4 RAM type.
Can You Reuse Laptops’ RAM in Desktop?
The laptop and desktop RAM sticks have different profiles.
Laptop RAM sticks are smaller and are thus known as Small Outline Dual in-line Memory Modules (SO-DIMM). Whereas desktop RAM sticks are just referred to as DIMMs.
Therefore, right out of the box, you cannot reuse a laptop’s RAM stick on to a desktop.
HOWEVER, with the use of certain adapters as shown below, you may be able to reuse a laptop’s old RAM on a desktop motherboard.
These adapter basically take the SO-DIMM of the same type and essentially increase their size AND the pin counts to match that of the desktop DIMM slot.
This method, however, is a bit flimsy and does not always work. Users have reported issues. More on this here: Can You Use Laptop RAM in a Desktop?
Again, the laptop’s RAM type, the RAM slot on the desktop’s motherboard as well as the Adapter’s RAM type support must all match.
Can You Reuse Higher Frequency RAM Sticks on Lower Frequency Supported Motherboard?
It is possible that you may have a higher frequency RAM stick at hand, but your motherboard only supports a lower frequency.
For instance, if you have an old or a spare DDR4 RAM stick with a frequency of 3200 MHz, but if your motherboard only supports a max of 2933 MHz (as shown below), then the RAM WILL Work, albeit it will be capped at 2933 MHz.
In others, it will NOT work to its full potential.
Mixing Two RAM Sticks – Reusing an Old RAM On a Motherboard with a RAM Stick Already Installed
It is also possible for you to reuse an old RAM stick on a motherboard that already has RAM installed but has an extra spare RAM slot.
In this case, if the newly inserted RAM has a higher frequency compared to the RAM that is already installed, then the newer RAM will clock down its frequency to match the one installed.
All in all, the answer to the question “can you reuse old RAM sticks” is a resounding yes, but you have to make sure that motherboard you plug in the old RAM supports the same RAM type.
In case if you cannot reuse your old RAM sticks, you can always sell them off or gift to a friend, family or donate to a local school.
Also Read: Where is RAM in Device Manager?