> From: Brian J. Beesley [mailto:[EMAIL PROTECTED]] ... > To get a real feel for this "value for money" question, > surely you have to factor in the system depreciation > cost i.e. the difference between the purchase and > residual values plus the total cost of the power > consumed over the working lifespan of the system. > Since new systems depreciate very fast, whereas systems > more than a couple of years old have virtually no resale > value, keeping an old system running is often going to > prove to be cheaper per work unit than buying a new > system which might process work several times > faster for roughly the same energy cost.
Indeed. Some old systems actually have a negative purchase price. I run several old DECstations which were given to me when I left Oxford University. As well as being of zero cost to me, they didn't cost the University anything to dispose of them. They are still doing sterling service as fan heaters to keep my study warm (it's not easy living at a latitude of 52 degrees north ;-) and happen to factor integers by ECM while doing so. My 21-inch Hitachi monitor cost me the grand sum of 4 GBP (approximately 6 USD) and also keeps my study warm when it's switched on. My moral is: don't over look the benefits of the "waste" heat if you live in a climate where you have to spend energy to keep warm. If you live somewhere which requires the expenditure of energy to keep cool, the balance may lie elsewhere. Paul _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
