I've started to post to this thread several different times and each time I decided against it for a couple of reasons. One, just sort of lazy and didn't feel like composing a lengthy tome.

And secondly, I really don't like posting anything that may be taken as a negative toward DC. :frown:
I have noticed over the course of the last couple of years that most (not all) systems that run DC (specifically BOINC) 24/7 tend to start running hotter and hotter. Now I know a big reason for that is the accumulation of dust and dirt. The first thing I always do when confronted with one of these hot running systems is to open them up and give them a thorough cleaning. That means brushing all the tight dirty spaces and fan blades and then giving them a thorough vacuuming and finally a high pressure blow out. This usually results in an immediate improvement but never as much as I would expect. Never do the temps return to the original ranges when the systems were new.
That has led me to believe that the electrical and electronic parts start wearing away over time. I know that aged and loose AC connections in a home are responsible for heated circuits and blown breakers. There must be a similar condition taking place in these computers. This is strictly my opinion and not backed up with any referenced source though I bet if I took the time to look I'd probably find articles stating just this fact. I do recall the topic of bulging capacitors being discussed many times before and heat was often mention as a possible cause.
So the old saw that running DC projects don't shorten the life expectancy of computers (very much) may be an exaggeration. For geeks like us who want a new system every six-months or so this doesn't really cause a problem. But a lot of people (like the "little folks" on TeAm Enterprise) tend to keep their computers for 3 - 5 years and even longer. I have had to shut down BOINC on most of these older systems because they just can't handle the load any more resulting in computer freeze ups, sometimes corrupted operating systems, etc. After I removed BOINC, all of these systems started running just fine and are now providing their owners continue good service. I remind you I'm not trying to knock DC but I'm just reporting my experiences.
I've been keeping up with temperatures of fairly new computers right here in my home and have been surprised to see the quick deterioration. Let me give a few examples:
I have a two-year old Dell SC400 with a 3.2GHz Pentium4 that now (after a thorough cleaning) while running BOINC has a CPU temp that hovers between 72C - 74C. :Q When BOINC is not running this system runs around 47C - 49C. I have moved this machine into my wife's office where she keeps the room temp at 70F (21C). This machine was previously in my work shop where the room temperature was about 3 - 5 degrees F higher. I had to stop running BOINC on this machine in my workshop. I observed CPU temps while running BOINC (in the workshop) between 78C - 82C. I made an interesting observation that I have not seen reported elsewhere. It seems that computers have a spike in CPU temps when BOINC if finishing a WU (or two), transmitting the results, downloading fresh WUs, and is getting started on the new WUs. I have observed this on many different systems. This particular computer (while running in my workshop) would spike up to 85 - 90C and then freeze up and crash. Normally I wouldn't discover the problem until after several days went by.

After awhile I gave up. That's when I decided to move it to my wife's office and replace her Dell 430SC, 2.8GHz P4 that I moved on to my grandson. I have just started running BOINC again on this machine on a trial basis. I have it set to use the BOINC Preferences meaning BOINC stops upon any use and does not startup again until 3 minutes of non-use. So the jury is out.
A machine that
BadThad is thoroughly familiar is about one-year old. It is a custom built machine with GOOD cooling that is running a PentiumD 2.8GHz on an Intel Motherboard and therefore NOT overclocked. I am actually using it as my primary workstation. Using the BOINC Preferences also I have observed this computer while running BOINC has CPU temps between 63C - 65C. When BOINC is IDLE the CPU temps range between 46C - 48C. The increase in temperatures when running BOINC is amazing!
A third example is a six-month old PentiumD system in a case with VERY GOOD Cooling parameters. This is a 2.66GHz PentiumD that I have overclocked as high as 4.0GHz when it was new. I have it running BOINC 24/7, always on. Over the course of the last few months I have had to slow this computer down more and more as the CPU temps started climbing. It is currently running overclocked at 3.65GHz and its CPU temps range between 62C - 65C. There is a drastic drop in CPU temp when BOINC is turned off. At idle this machine's CPU temp run between 42C - 43C. That is a 20C climb when running BOINC.
Maybe this worsening temperature situation I have observed is unique to Intel Pentium 4/D CPUs? I don't think so because many of the "little folks" computers that I have had to remove BOINC were AMD systems. I never did a thorough examination of the temperatures on those old computers but I bet the worsening temperature situation over time was the culprit there also. This temperature problem might also be the reason Intel has created the newest Core2 Duo type systems to run at lower speeds and also lower power consumption levels. It would be interesting to see if any AMD users have observed similar experiences. Or maybe this is a BOINC issue? Does BOINC use CPU more heavily than other DC Projects?
(If you read all the way through this, you deserve a gold star.) :laugh: