Different RAM sizes
Different RAM sizes
Hey! Your current 16GB RAM is single-channel, but adding an 8GB dual-channel unit should work if it matches your system requirements. Just check compatibility and ensure the total capacity fits your needs.
For dual channel setup, all sticks must match in size and speed. With a 16+8 configuration, RAM can operate in mixed mode, meaning half of the 16 GB stick will use dual channel while the other half runs in single channel, and the remaining sticks stay in single channel.
It seems some AMD setups support this too. However, I don't suggest it. Even with flex mode enabled, only half of the memory will function in dual-channel (or about two-thirds). @op, as I mentioned earlier, use two identical sticks with matching speed, latency, etc.