Yes, have been using Sensodyne for years. Haven’t had sensitivity issues in a long time. The toothpaste with Novamin works better and has other benefits, but is significantly more expensive than the Pronamel line (also available at Costco!) which is cheaper but also effective against sensitivity imo
Try checking if your shampoo or bodywash has Sodium Laurel Sulphate. A lot of people including me are allergic to it, and it can cause itchiness. There’s a lot of options out there free of SLS, so try using products without it.
Have you monitored the temperature at all? If it shuts off after 1.5 hours of gaming, that sounds more of a heat issue than power. It sounds like maybe a lack of thermal paste.
Get something like CoreTemp and monitor your CPU temps while gaming.
Well, if he is a responsible fishing enthusiast, he should be putting the fish out of its misery by stunning it in the head right away. As mentioned in the article, this is still the best way to ensure that the fish don’t suffer