Partial dual-channel works fine.

Yes, you can add a 16GB stick, and you’ll get partial dual-channel — 8GB of the 16GB will pair up with the soldered 8GB, the rest runs single-channel.

This is called Flex Mode (Intel) or asynchronous dual-channel. Most modern laptops handle this automatically. Some benchmarks show a slight hit for memory-heavy tasks, but for everyday use, gaming, or even light video editing, you won’t notice.

The bigger question: do you need 24GB? If you’re hitting swap or running VMs, go for it. If not, 8GB is tight but adding 16GB is better than buying a whole new laptop.

Don’t overthink it. Just make sure the SO-DIMM matches in speed (DDR4/DDR5, same frequency).