When deleting all files etc, are you also emptying the Recycle Bin? This does require emptying to help the system run smoothly.
Test that the Anti Virus software is not causing the problem by turning the auto update off for a short time.
Dell XPS 13 9370 (2018) review
No need to scan sketches into your computer with Moleskine's new smart pen
Streaming : Netflix ou Amazon Prime Video ?