Back in 2006-2009 I was just starting my adventure in to building PC's, as soon as the price of the new hardware hit my budget I would upgrade.
Nothing was planned. I spent and wasted money.. yes I got experiance in exchange but if I was more organised.. wow I could have done so much more. PC building great and all, but there is a life outside, and going to the cinema every so often should be part of my plans, just for the experience, going into town to a cafe and get a few things at poundland.. just for fun..should be a regular occurrence. remind myself why I do what I do by doing something different.
Builders can upgrade often.. everything can be exchanged to another similar part. and you can do that all the year long. but if you're doing it and not seeing big improvements.. honestly..really.. you're just wasting money. you need a SSD and decent amount of RAM & 4 cores and you'll probably have a good windows experience.
This is where 'planning your hardware refresh' comes in..
Depending on what you like and the games you play.. you probably should be thinking 4 years, when you do a build or re-build, plan for the event of 4 years, but YMMV all the jazz.. I try to every 3 years for good reason, because I buy compound cheap, like I bought 3 SanDisk SSD's cheap.. super cheap, and then found while they were meant to be all SATA3 all the way.. I suspect they have most of the parts but then a SATA2 controller chip inside >_<.. so they needed to be replaced after a year to sata3. my 660ti's great run! value for money! but now dead.. but even if they weren't dead I can't survive on 2gb anymore.. its just not enough vram.
My modded Skyrim is 2556 MB, no wonder i was getting such slow-downs and crashes!
All this means due to my budget, I should plan a hardware refresh every 3 years. Most companies go for four, including silicone manufacturers so you should too. Plan at the start of Nvidia or AMD or Intel's refresh*.. which ever you choose and like the most. if you are also planning a backup rig.. choose the other company to understand why and what they offer too, so your experience is educated with real world knowledge and not just nerd-internet-myths.
hope this was the nail you needed to finish that bookshelf.. a thought in the ether, sensible shoes.
peace.
Dava
* it's actually two years for cards, and four years for chipsets, but the cards are usually older branded ones from the last generation.. so every 4 years.