Most developers write their programs so that the app requests a certain percentage of the RAM available. More RAM helps, even if you use different sizes of RAM together. Yes, it might be enough to run your apps, but that doesn't mean it can't be faster. You don't need extra,' is common advice you'll find. 'This amount of RAM is enough to run the software. So, do RAM sticks have to match? Must you use the brand of RAM in every slot? No, but it's better if they do. Your RAM sticks will work together at the frequency of the lower stick by default. Overall, it's not as fast as using two sticks of the same size, but it's still faster than what you had before. The remaining 4GB of the new stick will run in single-channel mode. Once you switch on dual-channel mode (also called flex mode), it will perform as two 4GB sticks running side by side in optimal performance. For example, if your first stick is 4GB, you can still add a new 8GB stick.
However, this doesn't mean you can't use different size RAM sticks together. That's why it's best to use the same RAM model in all slots. For optimal performance, your RAM should use the same voltage, and their respective controllers should play well with each other and the motherboard.
RAM works best when paired with matching hardware.
