Check dual-channel mode with CPU-Z before upgrading.

Yes, and it takes 30 seconds. The easiest way is to download CPU-Z, open it, go to the Memory tab, and look for “Channel #” – it’ll say “Dual” or “Single.” That’s it.

If you’d rather not install anything, open Task Manager (Ctrl+Shift+Esc), go to Performance > Memory, and look in the bottom right for “Slots used” and “Form factor.” If it shows two slots in use and the speed matches, you’re likely dual-channel. But Task Manager doesn’t always label it explicitly — CPU-Z never lies.

Also worth knowing: most motherboards require sticks in slots 2 and 4 (or 1 and 3) for dual-channel. If you have two sticks crammed in slots 1 and 2, you’re running single-channel. Easy fix before buying more.

Just verify now so you don’t waste money or end up with a bottleneck later.