1. Supply a Web Speccy. Read how at https://www.piriform.com/docs/speccy/using-speccy/publishing-a-speccy-profile-to-the-web
2. See how it fares with an Userbenchmark.com run. Share the result.
3. Consider removing the existing HDD or SSD and pop in a blank and do a clean install of the OS to see if it's hardware.
Recently, my 6 year old computer running Windows 10 64 bit, i7-3770 3.4 GHz, 16.0 GB memory, 1 TB hard drive (not solid state) with 300 GB free, NVIDIA GEFORCE GTX 1080 started running in slow motion.
The clock runs slow (about 2 seconds for every second to tick by). Videos and games run slow. The scroll bar is slow. Even holding the backspace button is slower than before. Things like typing, dragging windows around, etc occur at normal speeds.
Everything seems to be synchronous with the system clock. I already replaced the bios/cmos battery (and in the process reset it), but nothing has changed. I did the option in windows 10 to reinstall, keeping files, but removing programs. I also verified the latest drivers in device manager and have installed all windows updates.
Since it's all related to the system clock (seemingly), I wonder if anyone has any ideas. Scans of the hard drive and pcmatic scans of the system showed no errors.
Unfortunately, there was not a valid windows restoration point for me to go back to. It seemed to happen randomly one day, not after some installation of software or hardware unless Microsoft was working behind the scenes. My thoughts were either a driver issue, cpu issue, or possible hard drive issue (but the hard drive wouldn't seem to explain the clock).
Appreciate any thoughts or recommendations for further scans, thanks!

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