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ccsccs7 · Mar 18, 2003, 04:24 PM

I have a PM 7500 that originally came with a 100MHz 601 processor. I purchased a 9500-only processor card which worked in it except for software upgrades, at which poing it would freeze up and crash (Now that I think about it could have been the CDROM as well, which made that problem worse, I believe it died, but I want to check it again, just to be sure). I purchased another card which is not supposed to be 9500-only, but I'm not sure if I'm using it now. I might be using the 9500-only card. I just checked, it doesn't say "9500 only" on it, but I might have overlooked it.

Anyway, I'm now experiencing crashes, even when not doing a software install, and after a while the machine refuses to boot or even chime! After turning it off for a while, it will boot again.

Could the use of this card cause real damage to the logic board? I'm not even sure if I could just get another processor, as I'm afraid it might have the same problems.

TIA

zac4mac · Mar 19, 2003, 08:24 AM

What speed are the proc cards supposed to be? Anything that was designed for a 75-85-9500 should work, with the exception of a couple of 9600 only boards that only work there. Essentially any 604 or 604e, 233 MHz and below will work. I'm pretty sure Apple OK'd the MoBo from 40-50 MHz, I got my 8500 up to 56.8 before it started getting flaky. My experience with 75/8500s is they are very touchy with respect to RAM and L2 cache. The whole reason I have a 7500 is to debug RAM troubles with my 8500 - much less painful. My 7500 came with a 601-100, but now has a 604e-233, the 8500 was a 604-120 and now has a G3-400 OC'd to 454 with interleaved EDO RAM. Fairly stable for an OS 9 Mac(lokked up yesterday for the first time in a month), used daily for iTunes, SETI and PhotoShop.

DrBoar · Mar 19, 2003, 01:57 PM

Got a 200 Mhz 604E CPU and a 256 k L2 from a G3 upgraded 7300. The CPU worked like a charm but the L2 locked up the computer, did not even boot! Why the L2 could run on a 50 Mhz bus on 7300 but not a 7500 I do not know. Also tried a L2 from a 7600/132 also a no go. I was lucky that the 7200 that I had upgraded with a 512 k L2 could be used as a donor and that 512 L gave the 604/200 a substantial boost.
Try removing the L2 to see if it boots
The 7500 is a very nice computer but it pickyness with the L2 (the 7600 is the same) is a source of irritation.

ccsccs7 · Mar 20, 2003, 03:18 AM

I tried removing the L2 (I believe I did, with all those slots and modules, it's a bit hard to tell. It's the smaller one between the larger bank of DIMM slots, right?) It still froze. I did add two 128MB DIMMs, maybe that's the problem. I must say, however, that before I put it into storage (the garage), it was working OK. I'd installed BeOS and was working on getting Mac OS X installed using XPostFacto. I lost the hard drive partitions (needed to be reformatted, could have been due to all the freezes while trying to install Mac OS 9).

The battery too might be dead. It keeps resetting to the old time (as in pre-Macintosh time).

Oh yeah, I know the card I'm using now is 150MHz 604e. I just ordered another card on ebay, a 225MHz 604e. It was designed for the Supermacs, I think. I hope it's not too high on the architecture scale.

ccsccs7 · Mar 24, 2003, 06:49 PM

OK, update time:

I tried removing the 128MB DIMMS and the l2 cache. It worked! I was finally able to install Mac OS 9 onto the hard drive. When I put the 128MB DIMMS in, it still worked! I guess it was the cache.

Processor card was fine. Even the SuperMac card works, just had stuff in the wrong place that keeps me from closing it all up. (Anybody interested in it?)

Thanks for the help. Now I know I can invest in a G3 or G4 upgrade wintout worrying about whethere or not it will work. (Just have to hope that doesn't fail.)