i used to have a thinkpad x200 with an core 2 duo processor and it was fine, but i wouldn't recommend it anyone. maybe i'm biased, but sometimes it's just neat to have a slightly more modern processor. one thing for example is, that im addicted to youtube and i want the website to work properly, which is just not possible with a core 2 duo. it will overheat all the time, when playing normal videos in the background. you can argue all you want, if its necessary for anyone to use youtube or similar bloated websites, but you have to admit, that sometimes it's neat to have the ability to run that when needed. also, video playback in mpv and compiling source code, are both things i personally had problems with too on that machine. it works, but it does so barely. my argument is simply, that the ability to do all those things is good to have. processors that fulfill those requirements, to do the things listed above smoothly, don't need to be the newest and priciest chip released. ivy-bridge and sandy-bridge intel processors do the trick just fine.