To keep on the safe side, Microsoft's install setup saves a full copy of your current Windows installation (that's the Windows.old directory right there), and while this will come handy in case something goes wrong or you need to revert back, it will also occupy several gigabytes of precious storage.
Storage Technology Corporation?
The subject of who first invented the USB flash drive is contested, but most attribute it to IBM
Not the BFG. That first gigabyte sure was heavy!
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Although solid state drives have steadily increased in capacity, so too have the size of game installs. Today's triple-A titles commonly occupy upwards of 20GB with many approaching or exceeding 60GB, especially after accounting for downloadable content. Ironically, it's often these large releases that benefit the most from the improved load times.
TSer Cycloid Torus is wondering how much he would benefit from buying an SSD. He doesn't need a speedy boot-up, but his current drive does load Fallout 4 levels painfully slow, raising the suspicion that it might be time to upgrade. Can he expect a performance boost anywhere else? Maybe it's best to go hybrid?