As it's a Laptop I'd be surprised the cmos battery has failed as the normal battery will keep the time and date etc. 'live' anyway. Same as a desktop shut down but mains still on. My personal opinion, for what its worth, is that it is a hard drive is failing.
Qualcomm Snapdragon 835 benchmarks: Antutu, Geekbench 4, GFXBench and PCMark results