3-4k? Do you mean 3000-4000 pictures or total file size? Most pictures of high definition are at least 1 MB each so I am curious.

Saving online is good but it might take awhile to upload or download. Get a portable external hard drive that gets its power from the computer. If you backup online you should make sure you can FTP right into your folder and not upload one at a time.

I had one that had an A/C adapter. It lasted less than 6 months. The power supply went bad, surged, and took out my data. This was 10 years worth of math resources for teaching math. Even the specialists couldn't save it. I am feeling the pain. (This was a western digital. I'm using a seagate now.)

And should you get a new laptop soon, most of them interface with the portable hard drives well without having to install software.