Fastest 68k machine for NetBSD, inc CPU upgrades

[Bunsen]

So I'm chasing up the parts to build a reasonable machine to run NetBSD/mac68k, and I'm looking for advice.

Alas, it looks like the Q950 is no go, and the fastest fully compatible machines are the Quadras 630, 650 and 800 (33MHz 040), or any other Quadra/Centris with a fast '040 upgrade.

In addition, support for CPU upgrades appears a tad iffy.

It would be nice (though not essential) if the machine could boot A/UX. Also nice would be support for a PPC upgrade, and Nubus/other expansion cards.

Here's the bit where you all chime in with advice and suggestions.

 

[Bunsen]

support for a PPC upgrade

I realise that means a machine with an 040 PDS, and if I want a fast 040 upgrade as well, one that goes in the CPU socket and leaves the PDS free.

I also realise it won't (likely) be accessible from NetBSD/mac68k [xx(] ]'>

 

[ChristTrekker]

Fastest in overall performance for NetBSD/mac68k is probably going to be the Q800. (The 840AV is crippled by slow SCSI performance, as I can attest. If that is ever fixed I'll be very excited.) That's also a good A/UX box. If you install a PPC upgrade, A/UX won't work. If you can't find an 800, a 650 would be my next choice.

If you're going to go for NetBSD/macppc, I wouldn't bother trying to build an upgraded 68k. Early PPC models are more plentiful, just as cheap, and faster.

 

[Bunsen]

I'm beginning to lean towards a 605/475 motherboard with a Quad-doubler, as that would fit in an SE case with one of my 9" monitors. I've also begun a wiki page to help clarify my thinking.

 

[johnklos]

You have a few good options for fast m68k Macs. One, you could get a Quadra 605 motherboard, like you said, with a QuadDoubler and a 128 meg SIMM for a 50 MHz m68040 with 132 megs. SCSI performance under NetBSD is good.

Even if you can't find QuadDoublers which point in the right direction, you can overclock them easily. I have two 40 MHz Quadra 605s set up - one is colocated in Los Angeles and hosts parts of macbsd.com, and the other is in a 1U case, colocated in New York.

Or, a Quadra 650 or 800 would be good, too, although you'd have to clock it at 25 MHz in order to use a QuadDoubler. Memory speed is very good and SCSI speed is good. I have a Quadra 800 motherboard in a Quadra 700 case with a QuadDoubler, and it makes for a very fast m68k machine.

 

[ChristTrekker]

I have two 40 MHz Quadra 605s set up - one is colocated in Los Angeles and hosts parts of macbsd.com, and the other is in a 1U case, colocated in New York.

Hi John! Are you new on this board, or have I just not noticed you around?

 

[paws]

Odd question, considering his joined date is right there on the left

 

[Bunsen]

Thanks for your advice johnklos. Since I began this thread, I've picked up two QuadDoublers - one with cache and one without.

 

[ChristTrekker]

Odd question, considering his joined date is right there on the left

Maybe he'd been around pre-deletion and just signed up again.

 

[z180]

You may need a floppy driver for NetBSD.

I recall that they don't have one.

 

[porter]

The only unix that can drive a floppy on 68k macs is A/UX. The floppy is not required for booting or installation.

 

[z180]

I got a SWIM III floppy driver from NUBUS powermac Linux,

but since NetBSD doesn't support my 6100 I can't hack NetBSD for it.

 

[johnklos]

I did have an account here ages ago, but the system didn't have record of it. So yes to both questions.

I've been having fun using m68k machines for various purposes - a Quadra 605 motherboard can be fit nearly anywhere, and even with a 7200 RPM IDE drive (on a SCSI-IDE bridge), a 40 MHz CPU, 132 megs of memory, and ethernet, they still take less than 25 watts total. Buying new hardware which has that kind of flexibility is EXPENSIVE!