Power Macintosh 6500/5500 Logic Board - minimum boot requirements?

[Trekintosh]

Howdy y'all,

I've got a PM6500 board in that should have everything it needs to work and I'd like to do some experimenting with it, but I don't want to have to whack it into a real chassis while I do so. What's the minimum viable product to make it a booting macintosh? Which voltages where, and which peripherals? I'm assuming that it just needs power, boot device, and a keyboard for soft power, right?

Side question: What's the cheapest solid state storage solution I can get going on one of these? I don't care about performance or capacity, I just want something cheap to get myself up and running outside of a chassis.

Thanks!

 

[DarthNvader]

What's the cheapest solid state storage solution I can get going on one of these?

IDE to compact flash or IDE to SATA. Chose the adapter that fits the price you want to pay and the drive you want to buy.

Both are pretty cheap solutions.

 

[aladds]

Do you have the backplane/harness to go with it? Without that I'd aim to just get power applied (3.3v, 5v, 12v) and video out somehow (a PCI card might be easiest) and boot from external SCSI. If you have the harness things are much easier, though!

 

[Trekintosh]

No backplane, no. I didn't realize the video output was in the edge connector on the 6500 too, oops. Guess I'll need to find the signals and cram them into a vga breakout

 

[chelseayr]

@Trekintosh yeah I think for sure that one big reason it went into the harness too was due to the aio's which precludes placing the monitor port onto the rear of logic board itself because that would make it awkward for internal displays otherwise

 

[Trash80toHP_Mini]

Never thought about the 5x00 as being a reason for the setup. It goes back to the Quadra 630 desktop. I think it most likely Apple was laying the groundwork the upcoming 6x00 tower case/subwoofer differentiation.

Backplane power switch, internal speaker connector and AMP for sound are on that assembly. 6x00 has a different, stacked board layout with higher output AMP and bass balance rheostat knob added.


edit: redux version of that board for 6x00 and 6360 with HD15 connector and the single resistor PowerPC VGA adaptation added would be a neat bit of kit I think? Should even work on the Quadra 630 and its descendants? I loathe hanging a switching VGA adapter off those cases. With vertical cooling exhaust that case can be very close to the back of a desk enclosure or the wall behind a desk.

Adding an internal stereo sound hookup with higher output amplification to it would add a stereo speaker equipped desktop re-casing an interesting proposition?

DA-15 to HD15 conversion makes space for a mono sub external jack for frog design inspired and AppleDesign variations on the TAM theme? There's a lot of space on the shelf behind the assembly if a bit more PCB acreage might be required?

malignant edit stream termination: thinking it's time for a bit of AI playtime and a hacks topic on this?

 

[chelseayr]

actually @Trash80toHP_Mini it was not only 4-digits but 3-digits models too

I went to quickly look it up for curiousity sake and hmmmm well heres the surprise as per everymac, the aio performa came out first before the non-aio performa did so that may explain why the harness was originally designed that way (then apple probably saw nothing wrong with the design hence retaining it all the way up to the final 5500/6500 usage)

performa 520 @ june 1993
quadra/performa 630 @ july 1994

so as you can see above, the aio performa very literally precluded the standalone performa hm?

 

[Trash80toHP_Mini]

Yep, that's why I said origin was the Quadra 630 sire (introduced three days prior to LC/68030LC equipped variants) of all I like to call the A/V Slot Macs/Architectures.


edit: 1995 580 would be the first changeover to A/V slot/6x0 series logic board for the 5x0 series, Great Logic Board upgrade/crappy downgrade from earlier 575's Trinitron CRT to shadow mask. Mixed bag from Apple . . .

So it goes . . .

 

[chelseayr]

as for regarding the internal crt itself hmm I can't help wondering if that was for to try further set "performa mac" and "power mac" names apart? but what would I really know tho
(even then everymac says that the power mac of that time could had been either a shadow or a trinton monitor both directly from apple themselves so hmmmm)

 

[Trash80toHP_Mini]

(even then everymac says that the power mac of that time could had been either a shadow or a trinton monitor both directly from apple themselves so hmmmm)

Didn't see anything like that, got linkage?

BTW, take everymac with a block of salt at least 25% the size of the monster needed at LEM.

 

[chelseayr]

heh well heres a coarse comparison of just four for now;
multiplescan 17 @ trintron @ march 1994
multiplescan 1705 @ shadow @ september 1995
applevision 1710 @ trintron @ december 1995
multiplescan 720 @ shadow @ november 1997

on a side note to above, the trinton dropping to shadow seem to correspond with how everymac quotes "This series provided originally a variety of entry-level to high-end displays. After the introduction of the high-end AppleVision Displays in August 1995, the Multiple Scan series was rebadged as an entry-level series and used lower-end CRTs." and they sure kept at that for quite an awhile given the november 1997 date

it would seem that when the macs moved beyond beige there was not much of any merit in trying to low-end the monitor itself anymore cue that all non-beige crt monitors available was very much trintron based, but taker my small opinion on that as you see fit!

 

[Trash80toHP_Mini]

I misunderstood, thought you meant an AIO released after the 575 was available with a Trinitron display.

What a shame. If any, they really should have put a Trinitron in the gorgeous, black PowerMac 5500 Director's Edition. Now THAT would have become a collectable, even if only 15" CRT in the 17" era. That black beauty's in the MoMA Industrial Design collection as is.


edit: for international members, that'd be New York's Museum of Modern Art.

 

[chelseayr]

ah yeah sorry I was thinking of standalone monitors when I loosely compared performa versus power macs, cheers still

as for regarding internal screen size, and regarding black macs .. I guess in theory someone could repaint an all-black imac (even the keyboards already have black keycaps so only the easier exterior shells have to be repainted) setup if they were crazy enough hm?? I know it won't quite be a collector mac but hey its 15" and its black?? heh!

 

[chelseayr]

@Trekintosh but anyhow you'll need the power supply and monitor-out pins at a very bare minimum, always could try tap out the disk drive (its a much smaller ribbon than either scsi or ide pins-wise) if you want to,unless you were going to stick to cds/diskimages alone

and in fair theory you could boot from an external hdd off the rear scsi port instead of having to tap the scsi/ide bus off the front edge connector if you wanted to test anything while not having a known good pci scsi card handy?

 

[Trekintosh]

I was gonna try a bluescsi v2 since it's easy to work with on the external port. I'd imagine it should boot. I just want to do some experiments with my Voodoo2, this wouldn't be a permanent setup. I've been kinda struggling to find a pinout for the edge connector, could someone help me out with that?

I also picked up the Apple External Video Connector as mentioned in one of the other threads on this subforum, so I don't need to make a VGA breakout cable for the edge connector, so that's nice.