Our HP ENVY TouchSmart 4-1118TU Touch Screen Ultrabook, purchased in 2012, came with Windows 8. Since we upgraded to Windows 10 it has been quite sluggish, so it was time for some investigation.
After the upgrade we allowed Windows to find any necessary hardware drivers automatically. Usually I'd get official drivers from the laptop manufacturer, but in this case HP only offered drivers up to Windows 8.1. At this stage Windows Device Manager indicated no hardware problems, and everything appeared to be working fine.
Looking at the specs for the laptop, its hard drive is described as:
"Intel Smart Response and Rapid Start Technology with 500 GB SATA (5400 rpm) and a 32GB mSATA SSD".This Intel technology is explained succinctly on Superuser.com. In summary, the small SSD is a transparent cache for the larger drive, and cannot be accessed as a separately drive. Knowing this, I suspected that the SSD was not operating as designed.
Returning to the HP support site, I confirmed that their Windows 8.1 downloads included the Intel Rapid Storage Technology Driver, and that this did not appear to be currently installed. I obtained a Windows 10 version from the Intel download site, the installation of which provided an immediate and profound performance improvement.
The lesson from this is that even if the Windows Device Manager does not show any problems, it does not mean that all desirable drivers have been installed.