Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!uunet!mcsun!ukc!axion!planet!prk From: prk@planet.bt.co.uk (Peter Knight) Newsgroups: comp.sys.ibm.pc.hardware Subject: Re: 16mhz 386sx running at 20mhz Message-ID: Date: 17 Aug 90 08:16:38 GMT References: <1990Aug7.230306.16069@agate.berkeley.edu> Sender: usenet@planet.bt.co.uk (Usenet News Manager) Organization: RT743, BT Research Labs, Martlesham Heath, Ipswich, UK. Lines: 40 magid@sandstorm.Berkeley.EDU (Paul Magid) writes: > I bought a 386sx thinking it was a 16mhz machine running at 16mhz. I >think the dealer made a mistake and put in the wrong mother board b/c it runs at >20mhz. The cpu is a sx that is rated at 16mhz; however, the chips and >technologies chip set is rated at 20mhz. The computer does run at 20mhz, and >has ami bios. Now for my question: By how much percent will my 386 chips >life be reduced? 10%, 20%? How long is the average life expectancy of a 386sx >chip in years? Should I be worried, and should I take the computer back and >demand my money back? >Paul Dear All, As this is my first outting on the net, I am a bit terrified of doing something wrong, but here goes. There is no difference between 16 and 20MHz chips, except that the faster chips get through the testers faster. However, the tests that are used compare the chip to its speed rating on the data sheet, which includes all kinds of interesting stuff about the pulse widths and how they relate to clock speed. If the board manufacturer does his own tests of incoming parts against not the data sheet but against his board specs, then there *should* be no problem. It shouldn't be done for where the cost of failure is more than an irate user and a crashed hard disk, of course. As for shortening the life, it could do. These chips run hot and the faster they are clocked, the hotter they get. The extra heat *could* shorten the life of the chip, but on the other hand PC's tend to fail because of wires breaking, solder joints giving up, boards disintegrating, etc. Peter Knight BT Research The views in this article are the author's own and are not necessarily endorsed by British Telecom. No liability accepted.