This is oriented to gamers but I think that it is interesting. It helps one answer the question: will an upgrade be worth the bother? <http://www.tomshardware.com/reviews/cpu-hierarchy,4312.html> [wandering elsewhere in the topic of upgrades] My last desktop upgrade (a couple of years ago) was from class 6 (Core 2 Quad Q6600) to class 1 (i7-4770). RAM capacity might also matter. In theory, my old desktop could have 8G of RAM but in fact it could not, so I installed 6G. My newer desktop should handle 32G but I only have 24G installed. SSD is so much zippier than HDD that it might be the first upgrade to consider. It seems to make a lot of difference with "modern" desktops like Gnome 3, Unity and Windows 8.x and 10. Make sure that you do backups.