LIN@Mit-Mc@sri-unix (11/20/82)
From: Herb Lin <LIN@Mit-Mc> can anyone tell me about what i should do in the way of diagnostics when i actually open the box that a new computer comes in? it seems there should be diagnostics that could give the system a workout BEFORE marginal components fail when out-of-warranty. any suggestions for (a) home-programmed tests, (b) diagnostic packages, (c) hardware diddling, (d) anything else? how long should these things be run? also, what is the "recommended" factory burn-in time for components in testing? clearly 200 hours is better than 48, but how much better? i'll post answers to the list. thanks.
LIN@Mit-Mc@sri-unix (11/22/82)
From: Herb Lin <LIN@Mit-Mc> Date: 20 November 1982 08:31-EST From: Charlie Strom <CSTROM> To: LIN Re: diagnostics for new computers, fresh out of box Sudden infant mortality is surely a very common occurrence in the microcomputer field. Memoery tests are very useful; the best I have seen is called the Rasmussen Memory test (MEMR2) from Lifeboat and is most likely available from them for a modest fee. There are also a plethora of public domain memory tests available in the public domain and they are generally useful for "hard" errors only; I have seen several instances of bad memory where the mory tests insist that all is well. Those that exercise the memory at full speed are the best. Look at one called WORM and another called UMPIRE (both in the public domain .) I did just have ocassion to repair a CCS 16K static board on which a 2114 went bad after about 18 months of almost daily use. This is the exception. The best way to burn in the system is to use it in normal operation intensively for a while. I find that the real life conditions will show up any faults much more effectively than the so-called test programs. If your machine runs WordStar for example, chances are that there are no problems. I will leave comments re disk drives and other components to others who are more knowledgeable about them. Regards, Charlie
LIN@Mit-Mc@sri-unix (11/22/82)
From: Herb Lin <LIN@Mit-Mc> Date: 20 Nov 1982 at 2046-CST From: mknox at UTEXAS-11 To: LIN Re: Reply to: diagnostics for new computers, fresh out of box To answer your question about burn-in; 48 hours will catch most of the 'infant mortality', the fact that new parts are much more likely to fail than ones that have been in use for some time. I would say that 200 hours would buy you only a 5% to 10% maximum increase in reliability. The military only requires 160 hours of burn-in (at rated temperature) on full 885B screened parts for applications up to and including deep space probes where service calls are VERY expensive.