2 GB hard drive in SE crashes a lot

[Ra226]

My Mac SE is pretty flakey (crashing randomly with different errors each time), sometimes as often as every 10 minutes.  It came with a dead 20 MB hard drive but I managed to find a 2 GB drive in (smallest I could find) and got that up and running.

I'm wondering if the drive is drawing too much power and causing my issues.  Any other theories?  And is it safe to turn up the voltage on the analog board just a bit to compensate, or should I just find a smaller/less power-hungry drive?

Thanks!

 

[unity]

If anything, the more modern drive draws less power. Odds are it even has less platters (rotational startup weight reduced). I would not turn up voltage until you check it, but it could still be the issue. Do you have an external drive you can test with it?

This is where someone says it is the caps....

 

[trag]

This is where someone says it is the caps....

I don't think that the SE has much in the way of failing caps on the logic board. I could be wrong, but I don't think that going in the 68000 Compacts until the Classic. The power supply and analog board on the other hand have been known trouble-makers since Pina published his wonderfully useful books.

If the OP has a voltmeter, I suggest that he measure the 5V and 12V pins on the logic board to analog board connector while the machine is running and see if they're within tolerances. Also try it while giving the machine something disk related to do, maybe copy a big file.

Frequently, on these old machines, the voltage reads okay in idle but drops under load.

Also, there are the old standbys. Is the 2GB drive terminated properly? If the drive was pulled from an external enclosure or was a loose drive, it's entirely possible that its termination was not set prior to installation.

 

[Ra226]

I planned on checking the voltages but figured I'd ask first.  I had completely forgotten that SCSI had to be terminated--I'll definitely look into that.  The drive was from a box of old drives at work--I have no idea their history, though I assume they were old Mac or UNIX workstations.

Thanks for the pointers, I'll report back!

 

[techknight]

Yup. Two most common requirements. Steady voltages, and termination. 

 

[ScutBoy]

Might also want to check on boot partition size; I know the limit was around 2GB depending on the version of System software installed.

 

[techknight]

Yea. It has to be under 1.9GB. For anything under an 040.

 

[Ra226]

Hard drive is terminated correctly (single drive, with jumper on "TE").  It's listing 2,053,935k available, 44,558k used--which comes to 2049.3 MB, so that's interesting... I'm surprised it even let me partition it that size if the OS doesn't support it.  I used a patched version of Apple HD SC Setup to setup the drive as the unpatched version I guess doesn't play nice with non-Apple drives.

Voltages measured at floppy port, pins 5, 6, 7:

-11 V

+4.9 V

+11.5 V

Those are low, but what's considered necessary for reliable operation?

 

[bigmessowires]

Is there a specific reason you suspect the HD is the cause of the random crashes? Couldn't it just as likely be the Mac itself, due to logic board problems?

Maybe try removing the HD and booting from a floppy, to see if the system is more stable.

The voltages look fine to me.

 

[Ra226]

I only suspected the hard drive because it's not stock and everything else is.  I'll try the boot floppy next...

 

[olePigeon]

Try partitioning the drive to 1.5GB instead of 2GB, see if that helps.

 

[Ra226]

I'll give the repartition a shot, but I'm not sure 1.5GB will be big enough...

 

[techknight]

Lol. Thats why you create a second partition for the remainder.

Anyone here remember the G3 8.4GB days?

 

[uniserver]

yeah the 233 iMac has this limitation if i am thinking correctly. 

 

[techknight]

and the entire Beige G3 line as well. 

 

[CC_333]

But wasn't that when running Mac OS X? I seem to recall that the 8.4 GB limit didn't apply when using OS 9.

c

 

[Scott Baret]

Here's something to try. Remove the hard drive and run the machine only from floppies. See if the problems persist.

 

[Ra226]

I will when I get a chance, but the floppy drive is being real flakey right now and my Classic II (see other thread, <sigh&gt will no longer boot... So I'm kinda stuck now with no 800k boot floppy.  Oddly, the SE behaves pretty well while being used, it only tends to crash after being idle for a bit.  I almost wonder now if it's a bad screen saver.  Anyway, thanks for the advice, everyone--I'll work on it.

 

[Ra226]

After more testing, I've definitely narrowed the problem down to the hard drive.  I booted to a 6.0.8 floppy (actually, a 6.0.8 image on my shiny new floppy emu!) and then played a bit of Crystal Quest (the app was located on the hard drive, not the floppy).  Rock solid throughout.  I quit out (after getting to level 27   , let it sit for 15 minutes with no screen saver, came back, and things were still fine--right up to the moment I double-clicked the hard drive in the finder, when it immediately crashed.

I'm pretty certain now that the problem is the hard drive, and not only that, the crashes only happen after the machine has been idle for a bit.  My theory is the drive has some kind of sleep/idle state that it kicks into when not busy and then the Mac doesn't know how to wake it again and crashes.  Has anyone seen this before?  Is this a common feature of later SCSI hard drives?

Meanwhile, I'm hoping a workaround may be to just set a very short screen saver time and hope that's enough to keep it entertained in the event I take a phone call while using the Mac.  I'm also looking forward to trying the hd20 firmware for the floppy emu, which could also be a solution (though I'd prefer a working internal drive).