Old Units still has life

Well after looking at all my 2003 made units I amazed that old discard PC are still running today! The radio cards are starting to fail and as soon as I replace the radio with new units I can see that most of my problems were in the weak transmission of the radio cards. What I am really amazed that the old Compaq computer have been running 3 years now in the outdoor temperature under extreme heat and cold conditions. If they are running they should have no problems. I did however had some problems with container or units that were totally exposed to the elements. But to some up old PC are still working. Replacing radio card for a new version does not seem to be a problem!