[cebritt]

We have a Performa 6116 with 24MB of RAM (two 8MB SIMMs). When we try to increase the memory by installing a pair of 16MB SIMMs or 32MB SIMMs (which work fine in our PowerMac 6100), the Performa won't boot. We've zapped the PRAM with no luck. Any ideas? Is it a bad motherboard?

I had a Performa 6115CD that had an almost identical problem. I was at 24 MB of RAM for about two years. When I tried to upgrade to a higher amount (40 MB or 72 MB), the system would either not boot (blank screen) or display a Sad Mac icon on startup. I tried about six different pairs of SIMMs, all of which worked fine in other 61xx machines. I assumed it was a logic board problem, although a Mac Tech at CompUSA found nothing wrong with the logic board (other than the tiny little fact that it crashed with any RAM upgrade higher than 24 MB). Finally, I just gave up and resigned myself to being stuck at 24 MB.

Incidentally, at one point I used a clock chip accelerator on my Performa, which may or may not have affected the logic board in an adverse way.

Ehren Schwiebert
[email protected]

I have a 6115 as well, and used it for 4 months on the 8MB of RAM. Then I went with 24MB, no problems. After a year I upgraded to 72MB (and added 256kB of L2) and used that up until 2 weeks ago. That's when I got a Sonnet G3 upgrade (240MHz/1MB L2), and I yanked the old L2 out and I also added an A/V card I had from a scrapped 7100/80AV. I have had no problems with the RAM in any way.

Where are you getting your RAM from? I get all my chips from MacSolutions (including 128MB upgrade for my G3 desktop, 8MB for an LCII, and 256MB (2-2-2) for my brand new G4/450. I've never had a bad chip from them and have always gotten a decent price, fast shipping, and friendly sales people. Jeez! sounds like a commercial.

But to put it succinctly, I'd say you might be getting bad chips.

[Kenneth]

Hi,

The current configuration of my Performa 6116CD is 72MB RAM, Apple AV Card(2MB), stock 700MB HD, and MacOS 8.6. First, I ran this machine with 8MB RAM, then going to install a pair of 16MB RAM, and now a pair of 32MB RAM without any problem, I'm using the Viking RAM. Somehow I did try those PC 72pin SIMM RAM, but they didn't work. In conclusion, I guess these old machines cannot use PC RAM.

Hope this help


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"With technology in all corners, learning to unplug can be particularly difficult."

I think it has to do with the extra parity bit in the pc memory

I know this is obvious, but did you remember to hit the little red reset button on the motherboard after you installed the RAM?

[cebritt]

Originally posted by EhrenZoner:
I had a Performa 6115CD that had an almost identical problem. I was at 24 MB of RAM for about two years. When I tried to upgrade to a higher amount (40 MB or 72 MB), the system would either not boot (blank screen) or display a Sad Mac icon on startup. I tried about six different pairs of SIMMs, all of which worked fine in other 61xx machines. I assumed it was a logic board problem, although a Mac Tech at CompUSA found nothing wrong with the logic board (other than the tiny little fact that it crashed with any RAM upgrade higher than 24 MB). Finally, I just gave up and resigned myself to being stuck at 24 MB.

Ehren Schwiebert
[email protected]

Thanks. I was hoping someone else had experienced our problem, however, I was also hoping there was a solution. Since you had the EXACT same problem we're having, I'm thinking it may be a defective batch of Apple ROM cards. I've pulled the ROM card and the PRAM battery out of a 6100 that works and I'm going to try them in our 6116CD early next week.

Many thanks to all of you that have posted suggestions! I'll try them all and keep you posted...

Thanks, Carleton

[cebritt]

Epilogue: Yesterday, I tried everything that has been suggested with no luck. I plugged in the battery and Apple ROM card from a working 6100. I removed the battery for 15 minutes. I ran Tech Tool Pro to test the RAM. I burned incense. Nada.

There are two things that lead me to believe its either an Apple glitch or something on the motherboard:
1) Ehren's message. Exact same problem.
2) When I disconnected the SCSI ribbon cable from the motherboard, it didn't display the disk with question mark. The monitor stayed black.

Like Ehren, I've determined that our 6116 is stuck at 24MB. There may be a set of larger SIMMs out there that will work but I don't have the time to find them.

Thanks for all of your help!!!