on 1/8/01 Marc <[EMAIL PROTECTED]> wrote: > Have been discussing this off-list and wondered if any one else has > been having similar problems. > > The History : > Two different 2400s. Several different SCSI connectors (APS SCSI-Doc > adapter, generic SCSI L-shaped adapter, and even plain Apple > HD30-DB25 cable). > Two catastrophic crashes and fried hard drives. This can be due to momentary interrupts during disk reads, data transfers, caused by a loose cable. It can also be due to a bad SCSI cable--which happens much more often than you would suspect (too many cheap ones around, too). The SCSI adapters sometimes have bent pins which can create a short as well. Also disk driver (in)compatibilities (mainly 3rd party), systems losing their "blessing", are also issues that can cause boot failures or worse. > The Observation : > Lots of play between the HD30 cable or adapter, and either of the two > 2400s I use. This occurs whichever cable or adapter is used. Feels > like the actual socket in the 2400 is moving. My brand new 2400 died the first day I ever had it on a SCSI connection (possible short between pins or on the MB). After going to Apple/Rochester 4 times in a row, it's been OK ever since but I worry about free play too. I ALWAYS make sure my SCSI connector is inserted as deeply as it will go into the 2400 SCSI socket. > The Suspicion : > I want to suggest that movement or weakness at the point of > connection (the actual socket in the back of the 2400s) leads to > unpredictable SCSI connections. Possibly, but on a case by case basis. Actually I've inspected the soldering connection of the SCSI port to the MB and it actually looks reasonably strong. It flexes because it sits perpendicular to the MB. There can be many spurious causes of unpredictability. Most recently one SCSI Zip drive would fail to mount on my 2400 but another drive did fine. Neither drive exhibited problems on the DTs they were attached to. After successfully mounting the 2nd, I could also successfully mount the 1st despite multiple prior failures (incl trying Mount Everything, SCSI Probe and Norton to mount the drive--same Zip disk in both too--go figure). I suspected a bad cable but even that was disproved. My point is SCSI voodoo can really be due to any (or any number) of reasons. Not encouraging but you have to work methodically, consistently and carefully (preferably with all HDs using the same (Apple recommended) drivers and OS). > > That, along with all the warnings concerning hot-unplugging of SCSI > connections, I suspect this all to be the cause of the HD corruptions. If anyone hot plugs SCSI, they and the computer deserve to fry. Definitely an unequivocal no-no! Sidney Ho ---------- Duo/2400 List, The friendliest place on the Net! A listserv for users and fans of Mac subportables. FAQ at <http://www.themacintoshguy.com/lists/DuoListFAQ.shtml> Be sure to visit Mac2400! <http://www.sineware.com/mac2400> To unsubscribe, E-mail to: <[EMAIL PROTECTED]> To switch to the DIGEST mode, E-mail to <[EMAIL PROTECTED]> Need help from a real person? Try. <[EMAIL PROTECTED]> ---------- Dr. Bott | Great Duo & 2400 stuff including 10/100 Ethernet for 2400s! Dr. Bott | Duo Batts too <http://www.drbott.com/prod/alist/duo.html> NineWire | If they are cool enough to host this list... Digital Solutions | ...you should check them out! http://www.NineWire.com/ PowerBook Guy is | Click here! Everything PowerBook! | http://www.powerbookguy.com Midwest Mac Parts ][ <http://www.midwestmac.com> After-market parts for Macs. ][ 888-356-1104 ][ MacResQ Specials: LaCie SCSI CDR From $99! PowerBook 3400/200 Only $879! Norton AntiVirus 6 Only $19! We Stock PARTS! <http://www.macresq.com>
