Blue and White G3 crashes with new RAM

Question

Blue and White G3 crashes with new RAM

Sorry kinda long

I'm looking for some old school info from a fellow old school OS 9 tinkerer who used to troubleshoot one of these old birds back in the day.

Among my stable of computers, I have a Blue and White G3 running os9.2 that I still use with some old legacy apps (notably Macromedia Freehand and Director). I like keeping my old computers that have served me well (for the most part) professionally in my career up and running.

Thought I'd upgrade the old girl with some RAM - I had 3 slots filled with one 64MB (yes megabyte!) chip & two 128MB chips, and she's always plodded along decently, except I couldn't open 2 graphic apps at the same time.

So I bought four 256MB RAM chips —the most the BW G3 can handle according to Apple.com —from OWC (https://eshop.macsales.com/) a supposedly reputable Mac memory mfr. They were only $9 each!, used to be much much more. Then I carefully installed them, discharging static first, one at a time. After a problematic start - the monitor wouldn't turn on - and much plugging/unplugging cords, I got the computer back in operation and the memory to show up in System Profile and started using it.

If you remember back in os9, each app allowed you to set the memory allotment in the Info box, and I bumped up the allotments, careful to leave plenty of RAM (250MB) available for the OS.

To my disappointment, now the old girl routinely freezes up when working in one of my graphics apps.

I tried zapping the parameter RAM repeatedly but that doesn't help. And rebooting repeatedly.

I tried removing the RAM and reinstalling one at a time. I found that only slot 1 seems to like this new RAM. When I put the new chips in 2, 3 & 4 it crashes. I tried each chip in Slot 1 and each works ok, but filling more than 1 slot with these 256MG chips breaks things.

So now I've got 1 new 256MB chip in slot 1, and my 3 original chips in the other 3 slots and it works ok.

I'm wondering if there are other things I could try before I return this RAM?

Suggestions?

Posted on Jun 13, 2015 5:41 PM

Reply

Answer 1

Jeff

Level 6

12,058 points

Jun 13, 2015 6:23 PM in response to TheOriginal150mph

OWC should know that the B&W G3s can only use 256 MB DIMMs having (16) 128-Megabit chips on the DIMM — 8 chips on each side of the card. If your 256 MB memory cards have only 8 chips on one side of the card or 4 on both sides, then the chips have a greater density (256-Megabit) and may likely be causing the problems that you're having. Additionally, I'd want SDRAM DIMMs rated CL-2 (2-2-2) and not CL-3 (3-3-3).

Reply

Answer 2

Jun 15, 2015 6:33 PM in response to Jeff

Thanks for the reply Jeff.

Here's a scan of one of the four DIMMs. They have 8 chips on each side. I had to whip out the calculator to figure that means each chip must be 16MB.

You can see they're CL-2 2-2-2.

So, from what I understand you're saying, this is exactly what I should be putting in the G3, unless I'm mistaken....

Reply

Answer 3

Jeff

Level 6

12,058 points

Jun 15, 2015 7:35 PM in response to TheOriginal150mph

The label on the DIMM indicates compatibility. Did you press the CUDA button on the motherboard, after replacing the memory DIMMs? That's the very small black button located closest to the battery holder. Also, has this computer been sitting for an extended period of time, disconnected from electricity? If so, you should replace the 3.6-volt, ½AA lithium battery on the motherboard. Just be sure to install the new battery, observing the correct polarity. A dark display on startup ("After a problematic start - the monitor wouldn't turn on") is a classic sign of a very weak/dead PRAM battery. It can also cause other quirky behavior.

Reply

Answer 4

Jun 15, 2015 11:02 PM in response to Jeff

First I've heard of this CUDA. Some kind of reset? I'll pull it out and look for it. You're saying that I should install all the ram again and try pressing this button?

This computer stays plugged in and fired up regularly, several times a week since it was new, so it gets turned on and off a lot. But I hadn't opened it in years (not in an easy place to get to) and it was pretty dusty inside, so I vacuumed out the interior as much as possible without touching the wand to anything (except the fan and harddrive) - being careful to touch the frame repeatedly - and then blew it out thoroughly with compressed air before installing the ram. Was probably the first time the inside had been cleaned. Needless to say, I handled the ram excruciatingly carefully. So for years, one of the slots had nothing in it.

At one point, a tech from OWC suggested I rub a pencil eraser along the contacts so I tried that too.

Yes the monitor wouldn't come back on after the first ram installation and I had to pull the computer and monitor and everything out from it's tidy place in the corner with all the wires and converters nicely tucked away, then disconnect and reconnect everything out in the open one at a time. What a pain that was. It appears some cable jiggling may have been the solution to that, but it was an unnerving and depressing 30 minutes at the beginning! Now its all back together in its spot and seems to be its old self.

I can buy a new battery I guess - shouldn't hurt to try that if its not too expensive.

Something I recall from my first ram upgrade way back when - that there was something said about which slots to put which ram in, but I can't locate anything about that by Googling.

Reply