Very Serious Mac Classic Problem

7 posts / 0 new
Last post
Offline
Last seen: 16 years 10 months ago
Joined: Nov 10 2005 - 08:51
Posts: 6
Very Serious Mac Classic Problem

Hey everyone! I have a serious problem with my Mac Classic. I found this one a year ago at a thrift store. It had been abused. The hard drive that was already in it was dead. It has been in storage for awhile until I could get another hard drive for it.

I finally was able to put a hard drive in it, but found a serious problem. When I go to click on almost ANY program, it comes up with an address error. It's running System 7.1 (w/System Update 3.0), it has the RAM expansion card maxed out to 4 MB of RAM and a 40 MB Hard drive.

I have tried a fresh System folder, zapping the PRAM, rebuilding desktop, different System versions, booting off a floppy disk, booting off the ROM disk, taking the RAM card out, cleaning the logic board thouroughly, everything a person could think of.

When I took the RAM card out and ran it on 1 MB of RAM, it still gives me address errors on almost every program. I know these programs are 68000 compatible because I also ran them on a Mac SE. Here's what I do know:

- It's not a hard drive problem. This happens on a floppy and ROM disk.

- It's not a battery problem. It does this regardless of whether it's a weak or strong battery.

- I can sometimes get 1 or 2 of the programs to load by pressing the interrupt button and typing in G. Most times, it will cause a Finder address error.

I've got a bad feeling that it may be the onboard RAM that's went bad, but for one thing, it doesn't give a Sad Mac. For 2, I've checked the RAM using RAM Check and it tested ok. Maybe there's something I don't know about. Could anyone here help? If it is the onboard RAM, is ther anyway I can bypass it? The Classic will boot and run fine, except 95% of the programs I open will pop up with an address error System bomb.

I'd like to try to get this Classic going if I could. I hope it's not terminal so to speak. If it is the logic board somehow, would anyone here happen to either a spare Classic or spare Plus that works? I need a 68000 that works.

Thanks for reading my long post. I'd really appreciate anything you could suggest. Smile

Take care,
Tommy

grannysmith's picture
Offline
Last seen: 12 years 3 months ago
Joined: Dec 20 2003 - 10:38
Posts: 178
Classic woes

If the soldered-in 1MB of RAM were defective you might expect video problems, because of its use as VRAM in the 1-bit Classic AIOs. That you don't mention video trouble, and that augmenting/removing the expansion RAM makes no difference, confirms that it is unlikely to be a RAM problem.

What you describe is far more likely to be HDD-related. You didn't write explicitly that you had reformatted either HDD, and the symptoms are classically Smile those associated with corrupt logical structures. I suggest that you reformat both drives (if the old one will spin up at all), install new drivers as part of that process, and then only install new complete copies of your intended System. In this way you will know that a drive is zeroed, sectored, partitioned (into the invisible Apple partitions plus the visible data partition, the 'volume'), and with the nucleus of the file directory, intact boot blocks and so on. While you are there, so to speak, why not install a larger (160-250MB), more recent and maybe faster HDD, unless it is your intention to maintain the Mac in 'original' trim. Small drives are as cheap as chips nowadays. Good luck.

de

davintosh's picture
Offline
Last seen: 10 years 2 months ago
Joined: Dec 20 2003 - 10:38
Posts: 554
Easy Solution

Buy one of mine! I've got two very clean -- and working! -- Classics that you can have for the cost of shipping. See the post I put up last night http://www.applefritter.com/node/9330

If shipping cost is too much for you, I'll even go halvsies with you on it. I only want to see these machines go to a good home, and not the recycler!

Offline
Last seen: 16 years 10 months ago
Joined: Nov 10 2005 - 08:51
Posts: 6
I forgot to mention something

I forgot to mention something. I'm sorry for not mentioning it earlier. I always seem to forget something. A friend of mine let me use his hard drive to see if it was a hard drive problem. I swapped in his hard drive that came out of his Classic II. I put the same apps on his hard drive and tried to open them, it came up with the same address errors. But when he put the hard drive back in his Classic II, the programs would run (except for one, that only works with a 68000). He tried my hard drive in his Classic II and it loaded the programs without the address errors. I've also tried opening up the programs off a boot disk. I even tried booting off the ROM disk, still nothing. I formatted the hard drive in mine, installed 7.1, tried it again, still the same thing. I've tried different versions of System software, still no go.

That's why I tend to believe it's the onboard RAM. Any other suggestions? Smile

Take care,
Tommy

Offline
Last seen: 18 years 2 months ago
Joined: Jan 22 2005 - 20:20
Posts: 595
First, let me say...

First, let me say that I have absolutely no idea why your Classic is behaving this way. I will, however, add that I have experienced similar problems with a PowerMac 9500 in the past. Fortunately, however, my 9500 seems to have mysteriously cured itself. Or, then again...

Since address error problems first became apparent on my 9500, I have replaced the RAM, hard drives, and have updated the OS to 9.1. Did the 9500 cure itself? Your guess is as good as mine, but my 9500 no longer exhibits those most annoying errors.

grannysmith's picture
Offline
Last seen: 12 years 3 months ago
Joined: Dec 20 2003 - 10:38
Posts: 178
Hard disk woes

You may be one of the unfortunate very few to have a dead SCSI controller. If an alternative SCSI cable does not remedy the fault, you are driven towards the idea that logic board replacement is your only remaining course. (The assumption in this is that the HDD power cable is all right, in that drives do spin up.)

de

Offline
Last seen: 16 years 10 months ago
Joined: Nov 10 2005 - 08:51
Posts: 6
I'll try a different SCSI cab

I'll try a different SCSI cable, but I doubt that it's a SCSI controller problem. It does the same thing when the Classic is booted off a floppy disk and off the ROM.

Tommy

Log in or register to post comments