Things are going "not obsolete" at record pace. Meaning a computer has never held itself better than it does today. You can buy a high end gaming og today and still expect to be able to be able to play AAA games on decent graphics in 6-7 years. There was a time when your high end gaming pc could barely survive 2.

On the flip side, there's not a huge amount of money to be saved by buying used any more. Back in the LTT Scrapyard war days you could get entire computers capable of playing very decent games for almost nothing, people where practically throwing them away. Now, as computers hold up better, so does their value