I appreciate all the input. Since I find it impossible to impart a full understanding to close friends and family of the deep nature of my anal retention, I know it is impossible for me to impart such an understanding to forum fellows. So, I'll instead demonstrate how pervasive the nature of that retention by addressing what further suggestions have been made. As I've aged, I've tried to incorporate advice from those same friends and family to moderate my tendency to "provide eye-glazing amounts of information" on any topic, and tried to so moderate with my earlier posts. However, I am suspending that policy for the remainder of this post, so you may need to push your reading glasses into optimal position, if you've got 'em.

I live surrounded by farm fields on three sides, on which crops are rotated sometimes twice a year. So, a few years ago, during an annual service, I had my air system altered to prevent it from pulling in fresh air. I offset that by specific species of houseplants and carefully-timed once-in-a-while airing of the house. Part of the reasoning is I was getting the chemicals they spray on the fields, not to mention dust/dirt during dry periods, plowing and harvesting, pulled into my air system. I was also advised by my HVAC dude that I was paying to draw in and cool hot air in the summer and heat cold air in the winter. He was right; my bill power dropped 10% to 15% each heavy duty month of the year after he altered my system. It also did my allergies a world of good during pollen seasons.

I live alone, and so I am the only one that cleans my 1,300 square feet. I have two cats and a dust/danger allergy, and have been told by more than one that I have an obsessive relationship with my overpowered HEPA vacuum cleaner. To further address the cat hair and dander, as well as household dust levels, I have four similarly-oversized HEPA air cleaners positioned strategically throughout the house. The air cleaner that shares this office with the PC in question is designed for a room three times this size, and runs on high all of the time. Each is properly maintained (vacuum your prefilters often!). A convenient side effect is the cats hate this room. (They will only enter this room if I'm sitting at my desk eating grilled chicken.) Since cats hear at something like 10 times the volume we do, I imagine the air cleaner, and the overabundance of cooling fans in my PC's, probably sound like 20 jet planes all taking off inside their heads at the same time. Not only does this mitigate hair and dander, it gets me peace when I need to concentrate on work.

But I don't just count on the air cleaners. I also have my PC's on a schedule for disassembly and cleaning. PC's with heavy use, like the two in this office, are thoroughly cleaned every 90 days. The Vista Media Center in my living room is awake on average about 25% of the time in active use or program recording, so it gets cleaned every six months, or sooner if temperature monitoring indicates an increase in nominal heat (usually during summer months).

As to the temperature of various components in my PC's, my retention comes into play there as well. One of my PC's runs a particular model AMD Athlon 64 X2 which is notorious for overheating. When I first starting running BOINC, unlike the other PC in the same room (the one about which this thread was started), that Athlon would run at 100% load no more than a few minutes before approaching 80C and abruptly blinking off, regardless of ambient temperature. So I replaced its stock cooler with one rated twice the TDP specified by AMD for the processor, and it now runs 24x7 at 100% without issue and only approaches 30C core temp when the room temp goes over 27C. I can also determine the ambient temperature in this room or a case at any time because I use a digital thermometer, so I know exactly the temperature of the air that is entering the PC cases.

On the PC that is the subject of this thread, as with all the others I've custom built, I carefully choose motherboards/chipsets and components whose temperatures I can monitor (with utilities like SpeedFan) and choose cases designed for exceptional cooling. They also must have a filter (or I add one) on the front panel intake fan(s), and must accept multiple larger (preferably 120mm) fans. I learned some 15 years ago that building a PC to high-end gaming specs assures it performs well, on speed and cooling, no matter the actual, intended purpose.

The mini ATX PC case in question has a 120mm front case fan and two 90mm back case fans that where chosen for their high CFM and run at 100%. (That other Athlon PC's full tower case has two 120's in front and two 120's in back, since it also hosts a GeForce 9800 GT which pumps out heat running Einstein.) Whenever I have any problem, component temperatures are among the first datapoints to be verified. Components in this this PC, at its hottest, run at least 10C below critical levels. The temp of the components in this PC were all well below even those "top" levels when CEP2 started to error out. Remember two other CEP2 tasks, or FAAH tasks once I altered the profile, continued to run without issue at the same time that other CEP2 tasks were erroring out.

Since my last post, I've left the PC set to run at most 3 CEP2's at the time, and included FAAH in the rotation, and set to run at 100% of CPU's 100% of the time as long as non-BOINC CPU stays below 50%. I have also left it set at "Run based on preferences" rather than "Run always." I guess "the system" is now once again trusting my CEP2 workunits, because it has resumed validating completed units without assigning them to a second PC for validation/verification. Earlier this evening, I decided to push my luck and micromanaged the queue to get three CEP2's running at the time time, including having two of them actually start at the same time. They beat the crap out of my hard drive for several seconds, and suspending two FAAH tasks to make it happen sucked away a larger portion of my 8GB of RAM, but it all ran without issue.

So, as much as it goes against my nature to give up on any troubleshooting project, I am accepting and moving on. I will leave the profile for this PC set for 3 CEP2 at the time alongside FAAH. I already have my two other available PC's running BOINC -- the Athlon 64 X2 I mentioned running two CEP2's at the time, plus Einstein on its Nvidia GPU, as well as my Centrino Duo notebook running CEP2 and FAAH at 70% -- so I'm not exactly hurting. SNURK's forum graphic says I'm hovering just between 29 and 30 Gflops, and I've managed to clock 1.63 years since joining in May of this year (not including Einstein time on the one GPU).

If being such a to-the-core-retentive didn't make me a useful programmer/tester/troubleshooter, I might would seek professional help. Assuming I can manage to tamp it back down, I now return to my hopefully more-to-the-point forum voice.

I have been getting the error code 195 more and more often (once or twice a day lately), while processing CEP2. I finally got some time to look into it.

I am running Norton Security Suite. I had some issues with Norton missing some stuff (a year and a half ago), and my ISP recommended also installing the free version of Immunet 3.0 -- they said it would run just fine with Norton -- and it did -- for a while. I noticed that Immunet 3.0 was tagged as high resource usage when a CEP2 would start. I uninstalled it, and it has been over a week since I have had the 195 error -- so I guess that fixed the problem.

Some other, maybe contributing factors, on my PC, appear to be Skype. I was staying logged on with Skype, and that appears to be a resource hog when left running logged in. So I now only log in to Skype when wishing to make a Skype call.

I also noticed that one of the processes for my Dell 305W printer appeared to have a huge memory leak -- think it was a DLDT process -- googled it, and I noticed others have experienced the same problem. I uninstalled the driver, but have not yet been successful when trying to install the latest printer driver (bricked my printer, at least for the time being, but still working on it).

The other factor may (or may not) be that my PC came with Intel Rapid Storage Technology -- increases efficiency of hard drive usage (unfortunately, I do not have a RAID array). May be a combination of all these factors that were contributing to the 195 errors during the period of intense HD usage at the beginning of the CEP2 WU -- hitting the system too hard.

Others experiencing 195 errors probably have different causes, but the causes may be of a similar nature -- just wanted to throw in my 2 cents worth.