Original iMac 233... need advice w/ booting (and odd noise)

[wardsenatorfe92]

Hi everyone,

As I've posted in the conquest thread... you guys know I had an Indigo iMac G3 which suffered from case problems. Well I pulled some strings and ended up with an original 233MHz iMac today! Just need some help getting it up and running (I also posted this on Macrumors seeking help but I figured I'd cross post here as well)

Everything worked initially, noted it was upgraded to 160MB RAM and had Panther installed. I decided I'd throw in a 80GB drive because it still had it's original (and noisy) 4GB drive. Upgrade went fine, no problems. It even booted to Tiger the first time after upgrading (which I was VERY surprised!).

The second time I went to boot the iMac, I noted that it did not want to start. It would hang on the gray Apple (no spinning wheel). Well this isn't a problem, because I was destined to install OS 9 on it anyway. I turn off the Mac, put in a 9.2.1 retail CD and I can't get the machine to boot from it. I tried holding down "C", Alt, in fact it wouldn't recognize any keyboard commands at all except for resetting the PRAM. I finally got it to boot Open Firmware by holding down the interrupt button. I tried getting it to boot from CD in there and it says:

"eject cd DISK-LABEL: read of block0 failed

can't OPEN: cd"

Lovely. I didn't test the drive before the upgrade so I have no idea if it worked or not, but I was told the machine was in complete working condition when I bought it. I also made sure the hard drive was set on Master and it was, so I have no idea what the problem is. It almost seems like the CD drive isn't getting power at all (disk not spinning when I pop it out).

Any suggestions?

ALSO, Part 2: When I plug in the iMac, for about 10 seconds or less it will make a whining noise while it's off. It seems to disappear when it's turned on, but it seems odd as well. After you turn the machine off (depending on how long its been on) it seems to go away in 10 seconds but sometimes it will last as long as a minute or more until the unit is unplugged. I assume this is a bad sign as well?

Thanks for all the help.

 

[wardsenatorfe92]

(sorry for double post)

I put back in the known working HDD with Panther, and it boots again. What it looks like is that either the CD drive isn't spinning or else the lens is not working. I inserted the OS 9 CD and nothing happened. I ejected the drive and you can tell it's moved from it's original position, but it won't mount or boot from the drive. I also tried an Audio CD and had the same results.

I guess the cd drive is toast?

 

[markyb86]

Sounds like the cd drive is shot.

My sawtooth PSU fans spin for a few seconds whenever I plug it in if it's been unplugged for awhile ... I figured that was normal?

 

[Byrd]

iMac 24X optical drives are notoriously bad, but these days you should be able to get a replacement from something like a junked laptop (and perhaps a custom bracket). As a last resort, try a CD lens cleaner on the existing drive, blast out dust, make duplicates of the CDs you can't get to work on new, good quality CD-Rs.

 

[wardsenatorfe92]

I tried cleaning the lens with a dry q-tip and it appears that didn't do anything. If you want, I can post a photo of the drive while it's open. It also appears the lens is all the way at the far end of it's mount. I don't know a TON about CD drive's but I know that it should start reading towards the center of the disk... maybe the head is out of alignment? I don't really have any spare drives easily accessible so I can't test out another drive.

I also do know the CD's work, I've used the OS 9 CD recently on an iBook and the audio CD works too.

Normally in this situation I could just fire up another Mac and install the OS via target disk mode but naturally this is one the last mac's before firewire became standard. :-/

Also on the "noise", I really think it's coming from the CRT. I hate to think it's going to have problems with the PAV board but that could very well be too. I've done a little research and I've read that it's typical for older iMacs to make this noise when they are off and I've also read it could be a sign of that board going out. I swore I'd never buy a first gen iMac G3 but it's looks almost new, I don't think it was used a lot.

 

[wardsenatorfe92]

Does anyone know any more information on the "whining" noise I'm talking about? It concerns me because if that is a signal that the machine is going to fail soon, i don't really want to put anything of value into it. Like I said, it only occurs when the machine is either off (or in sleep mode) and it's plugged in. When you press the power button, the noise instantly goes away. Most of the time it only lasts 10 seconds after being plugged in (or turned off) however if it's been used for a while it will last longer.

I might be able to get a video of it if needed.

 

[LCGuy]

Sometimes a Flyback transformer will make a noise like that when it starts to pack on the years. Either that, or they constantly make a high pitched whine while in use.

 

[wardsenatorfe92]

Ah ok. So is it anything I should worry about or should it be ok for a while? I don't plan on using it daily but I don't want it to short out or burn up, if you know what I mean. xx(

 

[LCGuy]

Eventually, it will die...lets face it - these machines were never known for their outstanding display components. However its hard to say exactly how long it will last...like any other vintage hardware, it could die tomorrow, or you could get another 20 years out of it.

 

[directive0]

When I opened up my REVB iMac YEARS ago, I remember there was an odd display looking connector coming out of the main logic board chassis that connected to the monitor. I assumed this was an internal VGA cable. Is it possible to connect this to an external display?

 

[Gorgonops]

When I opened up my REVB iMac YEARS ago, I remember there was an odd display looking connector coming out of the main logic board chassis that connected to the monitor. I assumed this was an internal VGA cable. Is it possible to connect this to an external display?

Yes. The connector is a dumbed-down version of the old 15 pin (two row) Apple monitor connection that was standard during the Mac II/Quadra/Beige PPC years. ("Dumbed down" in the sense that it seems to lack the sense pin support of the original version.) A standard Multisync Mac-to-VGA dongle will let you connect a VGA monitor. (And run it at higher resolutions than the internal monitor supports, the exact limits depending on whether you have the optional VRAM upgrade DIMM installed.)

 

[markyb86]

Could you connect a 15-pin 12" apple rgb monitor to that then?

( I know this doesn't help the OP any )

 

[wardsenatorfe92]

GREAT NEWS!

I got a replacement CD-ROM drive from another G3 iMac on ebay, installed it and it works like a charm! Got it to play a Beatles CD first and now I am booting OS 9 from a disk. I'll be glad to have Panther off of it and OS 9 on it instead.

As far as the monitor connection, yes, it is a DB-15 connector for older Apple monitors. I don't have any other Apple monitors at the moment or connectors so I can't test anything that way. I believe it would boot with with an external monitor but you'd have to leave the bottom case off... the early iMac's do not have a door for the DB-15 connector.

The "noise" is still occurring, but not as long as it used to. It disappears a few seconds after shutdown now, compared to lasting 10 seconds or more (but then again, I haven't had it on a lot today). I was browsing through the system files and it appears the machine was last used actively in 2006, so it has probably sat in storage for 6 or so years. I don't know if it's possible, but that may have something to do with it making the weird noises when off. The PRAM Battery also still holds accurate date and time, only being a few days off when I arrived it. So I would believe that those "last modified" dates are pretty accurate. I think the machine was last used by a home school or a private school, and I know the guy who sold it to me had a bunch of these. Either way though, the shell is in practically new condition... I couldn't imagine it being used much.

I'll throw the 80gig drive back in later tonight and install OS 9, and report back with the results.

 

[Gorgonops]

Could you connect a 15-pin 12" apple rgb monitor to that then?

That's where the "sense pin" thing comes in. I've not tried it, but I'm fairly certain the answer is "no". The limits of that connector, in my limited experimentation with one of those Mac monitor adapters that let you "dial a res", IE, make a VGA multisync monitor emulate any particular Apple Monitors, seem to boil down to either detecting the iMac's build in monitor (which supports three oddball resolution/sync combinations) or the "Multisync" setting supported by later Quadras and PPC Macs. the 12" RGB doesn't even support fixed-frequency VGA scanning rates.

As far as the monitor connection, yes, it is a DB-15 connector for older Apple monitors. I don't have any other Apple monitors at the moment or connectors so I can't test anything that way. I believe it would boot with with an external monitor but you'd have to leave the bottom case off... the early iMac's do not have a door for the DB-15 connector.

Yes, it doesn't support dual monitors or anything.

Your built-in monitor's flyback transformer *will* fail eventually. It's inevitable. It's likely the only reason it works at all now is the machine sat in a closet for so long. I was given two Bondi iMacs all the way back in 2000 and one already had a failed flyback and the other was in the process of failing when I gave it away a few years later. (And I'd probably used a total of, I dunno, maybe a hundred hours during those years.) This is why ATX case/power supply conversions were so popular for these machines years ago. I did a power supply conversion myself... I never got as far as actually recasing the iMac motherboard because it dawned on me that an iMac wasn't any more useful in a new case than it was in the original.

I'll throw the 80gig drive back in later tonight and install OS 9, and report back with the results.

If you've never had a Bondi before, reacquaint yourself with their Byzantine quirks when it comes to hard drives. Short version: They're picky about which ones they like, and that "First 8GB" OS partition limit for OS X? Apply it to OS 9 installs too, or you might end up regretting it.

 

[markyb86]

I never got as far as actually recasing the iMac motherboard because it dawned on me that an iMac wasn't any more useful in a new case than it was in the original.

I legit LOL'd at this but it really is a good point. If you're using an iMac to use an iMac, better off in its own case I suppose. However I asked about that 12" rgb because I would be shoehorning the imac board into an empty LC case (or trying to) if my crt ever goes. But that's good to know its not worth trying really lol.

 

[LCGuy]

That's where the "sense pin" thing comes in. I've not tried it, but I'm fairly certain the answer is "no".

I can confirm that the answer is "no". I've tried my Rev. D with a Macintosh Colour Display, and it didn't give me an image. As mentioned before however, VGA Multisync displays work fine, and even Multisync Apple displays with the old-style DB15 connector just plug straight in. During Summer I connect my Rev. D tray loader to my AppleVision 1710AV in order to keep the heat down, and it works perfectly at the 1710AV's maximum res of 1280x1024 in 24 bit colour. The power LED on the iMac glows amber, and the internal display doesn't power on at all, which makes the machine run much, much, much cooler.

 

[Gorgonops]

I can confirm that the answer is "no".

Yeah. Not to say that sticking an iMac motherboard into a dead LC is a bad idea though, even if it won't work with the original 12" monitor. One of the reasons I never finished my repacking job (other than the general disenchantment with how quirky and limited the iMac's hardware is) was I never really found a suitable case. (I went so far as gutting several oddball boxes, including an old ISDN router and a SUN external disk box, but the iMac's motherboard is such an awkward shape I could never fit it into something small enough to feel satisfying. An LC should work however.)

I still have in my junk box an LS-120 floppy drive scavenged from an old PC laptop that has a standard laptop CD-ROM IDE connector on it. It would be cute to put something like that in place of the LC's floppy. (A regular LS-120 or IDE ZIP would work as a slave on the same IDE connector as the hard drive, if you couldn't find a laptop one, and it is also possible to adapt the 50 pin cable that runs from the motherboard to the laptop CD-ROM adapter board into the standard 40 pin arrangement.)

The iMac motherboard *does* have solder pads for a real Mac floppy, but I seem to recall that if you apply the mandatory firmware update to run OS X on it it disables the controller, thus the need to go IDE.

 

[CC_333]

The iMac motherboard *does* have solder pads for a real Mac floppy, but I seem to recall that if you apply the mandatory firmware update to run OS X on it it disables the controller, thus the need to go IDE.

I think it does disable the controller, unfortunately. I have a Rev. A or B model iMac, and I tried this, and it wouldn't work. Evidently, this particular iMac has been updated (I've never bothered to confirm that, however).
Eventually, maybe dougg3's ROM/Firmware hacking technique can be used to circumvent this issue. His G3 firmware project could be adapted to an iMac, probably.

I'm a little curious, If you need to update the firmware to run Mac OS X (which, by the way, doesn't recognize the old floppy drive anyway), does the update serve any other useful purposes, such as bug fixes and the like? It's conceivable that the iMac would function just fine without this update under classic Mac OS, if all it does is provide Mac OS X compatibility.

Who knows?

c