Soldered RAM vs SO-DIMM RAM: Soldered means no upgrade, SO-DIMM means you can swap it yourself

Soldered RAM is permanently attached to the motherboard—16GB stays 16GB forever. SO-DIMM slots let you pop out the old sticks and replace them with higher capacity ones. Thin laptops like MacBooks and ultrabooks often solder RAM to save space, while others keep the upgradeable slots. Check your model’s specs: if it says “soldered” or “onboard,” you’re stuck; if it says “upgradeable” or “SO-DIMM,” you can swap for a $60 stick instead of buying a whole new laptop.