Explorer can experience slow performance at times.
Explorer can experience slow performance at times.
are you using a storage device other than the primary boot drive? If so, particularly with an HDD such as a mechanical hard disk, it requires some initial setup to activate (begin spinning) whenever you need access. I've had a similar odd sensation when installing my SSD—would open File Explorer or download a file and hear the drive start up. This is completely normal behavior, though the only thing slowing things down should be File Explorer.
Hard drives pause when idle and slow down to reduce wear. If you try to use a drive after this period, it will need to restart, which explains the delay you're hearing. You can usually change this setting through Windows power options, though I'm not entirely certain.
Control panel > Hardware and Sound > Power Options > Edit Plan Settings > Modify Advanced Power Settings > Hard Disk Drive
It's normal behavior. As mentioned before, the HDD has entered sleep mode and will need to restart, which takes a short time. To prevent this, you can modify the sleep timer settings for your storage devices. This may lead to slightly more wear on your hard drive, though it's unlikely to be a major issue in a standard PC.