When it comes to RAM (Random Access Memory) or simply “Memory”, it’s not just all about how much you have!
While this is usually the most critical aspect of memory we also need to consider its speed and latency.
RAM provides a temporary data storage area for your processor to access so that it can carry out operations quickly and efficiently. The processor has quick access to RAM, but not other data storage areas (like your hard drive). Therefore any data which needs to be used will often be copied into this working memory area (RAM) for quick access.
Having enough working memory space is essential for quick operation. Without enough RAM capacity, your processor will need to retrieve information from other places in your computer, which can increase the time taken to perform tasks and lead to noticeable lag and increased loading times.
Memory is fairly affordable. The amount of RAM you will need depends on how you will be using your computer. In general, the more processing your computer will be doing, the more RAM it will need.
Parameters you will want to consider when shopping for memory include:
- RAM size – amount of memory, usually measured in GB. This is the most important factor when it comes to selecting RAM, and other specifications such as latency, speed etc are very much a secondary consideration for the average user. The size indicates how much data you can store in memory, so a larger number is better.
- RAM type – DDR3 or DDR4. DDR4 performs similarly to DDR3 however it achieves the same performance level at a lower power usage.
- Latency – The latency of the memory modules measured in clock cycles, which can be translate to time (typically in nano seconds). If you are building a gaming machine, this figure won’t matter too much on overall performance as it is generally imperceptible. It is often expressed as “CL” (CAS Latency), e.g. CL10, meaning a CAS latency of 10 clock cycles. A lower latency equals faster response.
- Speed – The frequency of the memory modules measured in MHz (also known as the number of clock cycles per second). A higher frequency is better.
- Brand – Choose a reputable brand with good warranty.
- Voltage – some memory modules require a higher than stock voltage to achieve their speed. Ensure your motherboard can support this. For example, DDR3L (which runs on 1.35 volts) is a lower voltage RAM type than DDR3 (which runs on 1.5 volts). DDR4 is lower again, running on 1.2 volts.
- Compatibility – Check if your motherboard officially supports the memory. This is a step than many system builders overlook. Check your motherboard manufacturer’s website for the memory part numbers they officially support in your motherboard.
Here you will find answers to some common questions about RAM which are often asked:
What kind of RAM do I need?
You can check what kind of RAM you have currently installed in your computer in two different ways:
- Download and install a diagnostic tool, which can tell you what kind of RAM you have installed,
- Open up your computer and look at the side of RAM stick (it should have the type: DDR2, DDR3, DDR4 written on it somewhere, or otherwise you can look up the specifications based on the model and brand).
Another guideline is to go off the year of manufacture, but it’s always best to double check the particular kind of RAM just to make sure you get the right one for your motherboard.
- Pre 2007: DDR2
- 2007 – 2012: DDR2 & DDR3 (some DDR2 still around)
- 2012 – 2015: DDR3
- 2016 onwards: DDR3 & DDR4 (DDR4 still rare at this stage, but becoming more popular with the release of Skylake architecture).
What is RAM stick ‘matching’?
Most motherboards have multiple RAM slots and can accommodate more than one RAM stick. It is common to install RAM in ‘matched’ sticks, which refers to having two or more sticks of the same model, brand and size.
The benefits of this is that you will not have any compatibility issues between matched sticks.
Mixing brands/models/sizes will generally work, but can often lead to instability and system crashes.
We always recommend installing matched RAM where possible. Stick with the same brand, model, and size of memory where possible, especially for larger RAM sizes (mismatching larger sized sticks tends to affect your system more severely).
If possible, purchase your RAM sticks at around the same time as well, as sometimes manufacturers will revise/upgrade their product lines.
Can I mix brands?
Yes, though it’s not recommended. The system will still work, but different brands could potentially have compatibility issues that can lead to instability or system crashes.
Depending on how much RAM your system is currently utilizing, you may be better off running a single stick of RAM than trying to pair unmatched brands.
In some instances where you do not have enough RAM then the additional RAM capacity may offer advantages that outweigh any compatibility issues that might arise.
Can I mix sizes?
RAM stick sizes can be mixed, but try to stick to the same brand/model if possible to avoid compatibility issues.
Can I mix speeds?
The speed of the RAM is measured in Hertz (Hz). We recommend all memory be the same model, and also same speed grade as well (same Hz) to avoid compatibility issues.
However, it is possible to mix RAM sticks with different speeds. Be aware that the motherboard will run at the speed of the lowest graded stick, so one slow RAM stick can limit the speed of all sticks installed.
Sub-timings also can matter even if the primary timings on RAM sticks are the same. Different brands may handle these sub-timings differently. You will get the best performance by using ‘matched sticks’.
Should I get 2 smaller sticks or 1 big one?
This is a common question that relates to the RAM configuration for a set memory size. For example, is it better to get two 2GB sticks, or one 4GB stick?
The answer depends on the user.
The advantage of having two RAM sticks is that you can get ‘dual channel speeds’ (a doubling of bandwidth), which can give a noticeable performance boost if you are using on-board integrated graphics on your motherboard.
However, if you’re running a dedicated graphics card, dual channel speeds on your memory may not offer any noticeable advantage.
In this case it’s better to install one larger stick, as this allows more flexibility for upgrading to a second (hopefully matched) stick later, while not taking up too many RAM slots on your motherboard.