I was realizing that even when a computer still working just fine, there is a period where it can be sold at a good price. After that the price will drop big time and it would be better to keep it and still using it than selling it, eventually you will end up with a piece of hardware that won't be competitive. I have a 2010 iMac, I was about to sell it for $1000 but the new iMac is coming out with a good price. Now, my current iMac will drop price big time. I am thinking in keeping it but I already have a 2008 Mac Pro as my "legacy" machine. I was realizing that each 3 years is a time to replace machines, specially in my case that I work with video and motion graphics. In my office I am using thunderbolt which is a very good technology, very reliable and any of my machines has it. Any way, I was just sharing this dissertation about this issue.