smaug@eng.umd.edu (Kurt Lidl) (08/11/89)
>| Has anyone run any 3/60's with 12 meg of memory and noticed system >| crashes, where there weren't any with 8 meg? I haven't checked yet to >| determine if it may be application specific, but using 3 different cpu's >| and 2 different cpu cabinets, and 4 different SIMMs, we get crashes on the >| 3/60 with 12 meg, and not with 8....I can't believe they all have bad SIMM >| sockets. Most crashes seemed to be memory parity errors, however. Sun >| tech support is unaware of any problem with the 12 meg value. Could an >| application do it? >| >| Curiously yours, >| Dick Mead <mead@hamal.usc.edu> >We upgraded our 2 3/60's to 12MB of memory by adding Clearpoint SIMMs. >We haven't had a single memory related reboot and it's been 8 months since >the upgrade. >Scott J. Kamin {att!uswat, isis, nbires, dunike} !onecom!sjk >TelWatch Inc. (formerly OneCom) (800) 669-1266 (outside Colorado) >2905 Wilderness Place (303) 440-4756 (switchboard) >Boulder, CO 80301 (303) 938-6726 (direct) I wish I could say the same with the memory expansion in some of our 3/60's here at the University. We have taken a Sun supplied memory expansion kit, put it in a 3/60 (expanding the memory from 8 to 12 megabytes) and have it fail to properly boot /vmunix. Normally, the system will not get to the fsck on the filesystems before it starts to complain about a memory failure. The worst part is that the problem is NOT with the memory SIMMS, but rather the motherboards. The same memory boards will work perfectly well with another 3/60. There seems to be no rhyme or reason to whether or not the motherboards fail to run 12 megabytes of RAM or not. Of the five machines that failed, we were able to get all but two of them to work properly with at least one combination of memory chips. This suggests to me that the memory is marginally too slow for the bus, or that some of the chips are marginal... A very irritating problem that was worked around (in most cases) by swapping around SIMMS until everything worked... ================================================================== == Kurt J. Lidl (smaug@bacchus.eng.umd.edu) (301) 345-6243 == == UUCP: uunet!mimsy!bacchus!smaug (301) 454-1526 == ==========="Amiga : The Computer for the Best of Us..."===========
jon@incsys.com (Jon Shultis) (08/22/89)
We have also experienced the mystery memory problem with 12 Meg 3/60's. We replaced a supposedly faulty SIMM, rotated all of the SIMMs on one machine, and replaced the motherboard, to no avail. Finally, our local SUN field technician tinkered with it and managed to find a SIMM that worked OK. I thought we had a unique problem, but given the frequency and flakiness of the behavior, I suspect your hypothesis about faulty timing design is right. Another 3/60 running 12 Megs had a different behavior, and I wonder if it's at all related. Periodically it would hand with all of the LED's lit and the screen black, or with a pattern of vertical stripes. This tended to occur especially just before the fsck during boot-up. We replaced the power supply, the motherboard, then the whole chassis. The problem occurs less often now, but is still there. Is anybody else having this problem? Regards, Jon Shultis
clh@uunet.uu.net (Chris Hermansen) (08/24/89)
In our (limited) experience of adding memory (Clearpoint), I have noticed that at least one of our machines has a very irregular set of connectors in the expansion slot. In fact, it almost looks as if someone dropped something on it! Take a very close look at your CPU board. I bent some of the connectors into their "proper" position with a stickpin...
richard@uhccux.uhcc.hawaii.edu (Richard Foulk) (09/08/89)
} Another 3/60 running 12 Megs had a different behavior, and I wonder if } it's at all related. Periodically it would hand with all of the LED's lit } and the screen black, or with a pattern of vertical stripes. This tended } to occur especially just before the fsck during boot-up. We replaced the } power supply, the motherboard, then the whole chassis. The problem occurs } less often now, but is still there. Is anybody else having this problem? I had almost the exact same symptoms after I added additional memory recently. I moved the SIMMs around to different slots a few times and things began to work just fine. I suspect the problem is with the connectors. They're not as robust as they should be. Richard Foulk richard@uhccux.uhcc.hawaii.edu