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P475/Q605 misunderstanding

onlyonemac

Well-known member
Hi!

I'm failing to understand exactly how this works. Apparently the same logic board was used for the P475 as for the Q605, but the Q605 had a jumper set. What I'm not getting is that the P475 ran at 22 (or was it 25?) MHz while the Q605 ran at 33 MHz. Does changing the jumper cause the speed change?

Otherwise what is the difference between a 22 MHz P475 and a 22 MHz Q605?

Thanks,

onlyonemac

 

finkmac

NORTHERN TELECOM
This jumper identifies the computer as an LC 475 or a Quadra 605.

Not much to understand, the G3 BW has a jumper block that has to be changed to upgrade the processor.

 
Last edited by a moderator:

mcdermd

Well-known member
But you better not move that jumper, OOM - then you'd be stealing something you didn't pay for.

 

uniserver

Well-known member
Yeah that jumper just changes the ID.

475 / 605 same baord… they both run at 25mhz.

however you can make a slight mod to them and they will run at 33mhz no problem.

viewtopic.php?f=8&t=19310

file.php


 

onlyonemac

Well-known member
But you better not move that jumper, OOM - then you'd be stealing something you didn't pay for.
You're getting back for my comment about you copying those ROMs!
I did pay for a Q605-it's the same as a P475, so there's nothing more to pay for. You mean Apple really made us pay a lot more for one jumper? What the heck!

Actually, I didn't pay for it. I got it out a skip.

 

mcdermd

Well-known member
The Quadra 605 and Performa 475 were different models so you only paid for one of them. It's not like both name badges came in the box.

 

Gorgonops

Moderator
Staff member
You're getting back for my comment about you copying those ROMs!
To quoth the Bard: "Durrrr."

Considering the fact you've admitted to using BasilsikII (which requires a copy of the Mac ROMs) you peevishly coming down on someone for copying ROMs in order to repair a machine that came with those exact ROMs in the first place it's impossible to escape the conclusion that you've gone a few steps beyond "The pot calling the kettle black".

Copying ROMs is standard procedure for repairing all manner of old electronics, from computers to video games to pinball machines, etc. Yes, if you want to get completely anal legally it's a gray area: copyright law permits the owner of a copyrighted work to make a backup copy *for archival purposes only*. (Which could easily be interpreted as forbidding the use of a copy for an emulator; once you fire up BasiliskII your "archival copy" becomes a copy.) By any reasonable interpretation that would mean it would be legal to, say, copy the ROMs in your Mac 128k, burn them, and set the copies on a shelf in anticipation of the day that the original mask ROMs might go bad. The gray area comes from the fact that most of the time when you're confronted with a broken machine that needs new ROMs you obviously can't copy the bad ROM. Therefore you have no choice other than to take a copy of an identical machine's ROM or buy a replacement part from the manufacturer. Which, in the vast majority of cases we're interested in here, no longer sells them.

Something tells me that no one's going to be hauling anyone before a judge for making a copy of a ROM a machine came with to repair it. For someone who's all anal about "preserving" original machines it seems like a peculiar attitude to have that if an original replacement part isn't available (at any price?) the machine should go in the dumpster even if making a perfectly serviceable copy of the missing part is trivial. Mask ROMs *do* go bad and in some cases, like the fragile ROMs found in very old Commodore PETs, working original replacements are *unobtainable*. You either burn an EPROM or the machine is dead forever. Is that what you want, all those precious old Macs chucked in dumpsters the instant an original component goes bad? Forget ROMs, what if a RAM chip goes bad; is it HACKING if you replace it with a chip that has an incorrect date code? What about those nasty capacitors? Should everyone make darn sure they replace leaky old electrolytic capacitors with equally aged (and equally rotted) old-stock painstakingly excavated from the back rooms of abandoned Radio Shack stores?

Sheesh.

 

uniserver

Well-known member
Be happy you ended up with the LC475, The q605 all though its a much better looking machine, has plastics that will shatter like bones a 90 year old women.

 

beachycove

Well-known member
The q605 ... has plastics that will shatter ....
Actually, the plastics in my Q605 seem just fine (just like my 840av, BTW). But I have also noticed that the LC475/LCIII cases seem to hold up especially well.

 
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