I have a Sager NP8651, and my secondary drive (HGST HTS721010A9E630) is starting to get bad sectors, so I'm looking to replace it with a Samsung 850 EVO. The current drive is 2.5"x9.5mm, and the 850 EVO is 2.5"x7mm, although sources I've found say this shouldn't really be an issue. Since I'm not really knowledgeable on hardware stuff, I'm looking for advice on how to replace and upgrade, and whether my plan is viable.
not an issue at all. the drive may, I cannot say for certain, come with a spacer like the one I linked above.
if the new drive were larger you would have an issue. as it is you can fill the void left by the 2.5mm with folded paper if needs be.
if the old drive had rails that secure the drive the void will not be an issue and will not need filling