Every 3 years on average. Had a Q6600 quad core computer a few years ago when they first came out then upgraded to i5 2500k in January when they first came out. I usually buy every 2 generations. But I don't see myself upgrading for at least 3/4 years. This computer has more than enough grunt to meet my needs for a few years. Only thing I would ever upgrade is maybe a new graphics card and some more memory. Gaming is the only intensive thing I do on the computer, everything else like web browsing, watching films and things like that you can do on virtually any computer nowadays.