I believe it was OSX Leopard that wouldn't work on my IMac. That was back before my teaching career crashed and burned. OU's teacher ed program used newer versions, but I was trying to set an older one up to use in my classroom. This would have been before 2008. I've had several machines last quite a bit longer. Had an H89 that my FIL built in the early 80's that was still going strong in 1991. HDOS and CPM. Was headed for Germany, and didn't want to run it on 50hz power. The Z90 machine was only a couple of years younger. Those were the machines I put myself online with when GEnie was new and hot. The hulk of a PC sitting off my right shoulder now ran for over ten years, with Windows 3.0 and then 3.1 on it towards the end. The computer I just replaced was only 4 or 5 years old. It's a Dell Inspriron 3668. Win8, IIRC. Won't upgrade (if such it be) to Win11 since it's not got a late enough generation cpu. Though that one may have been a video card problem. I'll be trying it out again here in the next couple of days. May start playing with Linux on it if it will still run with out the video card. Got a 3D printer that could probably stand to not be connected to Windows machines.What hardware has been made obsolete by software? Yes, after several years the updates aren’t available for older machines. I’ve never had a pc last longer than 3 years.