I tend to treat computers as commodities, buying the best band-for-the-buck box when I need one. I tend to keep a couple desktops running at all times and use them as file/print servers. When I buy one, I turn it on and leave it running 24/7. Load it up with everything important to me, so both servers have my data on them. They usually stay running for about 4 years like this, and so I buy a replacement after a couple years and put it on the network. This gives me some redundancy and keeps my important data in several places. I also keep a couple laptops running and connect everything with a wireless network. The laptops are nice when you have to travel, plus you can work from your easy chair in the stereo room.

I don't pay the premium for cutting edge processing power unless I really need it. Doing graphics work is one place you really need it. I did graphics work for a while in the 1990's, so I had an Inmos parallel processing network and a Targa graphics card. But usually, I get systems that are a bit back off the cutting edge. Cutting edge costs a lot, and give it three months and the price is substantially reduced. One thing though, gamers often do get systems that are optimized for graphics and processing power. Look at the graphics board and make sure it has the resolution and speed you want. Look for deal on systems that are optimized for graphics and gaming.