At 9:21 -0600 12/14/02, Jeremy Derr wrote: > >Here's how a firmware update works... there's a rewritable EEPROM on >the logic board that holds the Boot ROM (aka Firmware). The firmware >update erases that chip, then writes the new Boot ROM into it. EEPROMs, >unfortunately, can only be erased and re-written a set number of times >(usually somewhere between a few dozen times to a few hundred, >depending on type). > >If the 'erase' mechanism of the EEPROM is damaged, it can fry the >EEPROM when the firmware update sends the 'erase' message. If the >'write' mechanism is damaged, you get an erased EEPROM that doesn't >have (and can't have) any Boot ROM. If the EEPROM has simply used up >its share of 'writes', you get the same affect... an empty EEPROM and >no boot.
Jeremy, if I understand what you are saying here, Apple seems to have built in a "expiration date" for their machines. Even if this was unintentional, Apple should fix the computers as a warranty repair (and good customer service) since the failure was a direct result of Apple using "defective" EEPROMS and the Apple firmware updates. If, as you say, " EEPROMs, unfortunately, can only be erased and re-written a set number of times (usually somewhere between a few dozen times to a few hundred depending on type)", Apple should have used EEPROMS that have a high re-write rating, since they can't tell how many firmware updates they will be issuing over the years ahead. Here is a question: will the firmware update work on a new empty EEPROM? If so, then it seems that putting in a new EEPROM would be the way to go, unless the EEPROM alone costs more than a new logic board. Sincerely, Dennis -- The iMac List is sponsored by <http://lowendmac.com/> and... Small Dog Electronics http://www.smalldog.com | Refurbished Drives | - Epson Stylus Color 580 Printers - new at $69 | & CDRWs on Sale! | Support Low End Mac <http://lowendmac.com/lists/support.html> iMac List info: <http://lowendmac.com/imac/list.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive: <http://www.mail-archive.com/imac-list%40mail.maclaunch.com/> --------------------------------------------------------------- >The Think Different Store http://www.ThinkDifferentStore.com ---------------------------------------------------------------
