"ultimate" 68k machine

[Bunsen]

I googled some 660AV motherboard images and came to the same conclusion. I also came to the conclusion that moving the drive might make it possible.

 

[SiliconValleyPirate]

no onboard video? bzzt... q950 has very fast onboard video

Sorry, I must have been thinking of something else...

Out of the box doesn't come into it - we're talking ultimate here. With the 50MHz upgrade I'd bet they would bench at least equally as fast in every respect, but the 950 is more expandable.

I doubt the RAM latency will look as good on a 950, but you are probably right when you say it'll be *as* fast. The point is to have a 50 megaton bus next to your desk that only performs as well as an 840av seems a tad pointless to me, unless you have a very good reason to need 6 Nubus Slots (the PDS slot presumably would have the CPU card in).

Feature for feature, a tweaked 950 creams a tweaked q840av (I think there was a newer upgrade for the 840av - but try finding it). Even the Q800 beats the 840av as it at least had a PDS slot (and could possibly take the 950 upgrades as it operated at the same clock frequency).

You use up the 3 NuBus slots in an 800 just adding features the 840av has built in, leaving a fat zero expansion slots for anything else useful that you can add to the 840av. That's hardly a very strong argument

Most of the differentiators named above were either never used or were inferior solutions anyway.

Load up Adobe Premiere 2.1 and hook a VCR to the 840av and tell me that again. I follow that the DSP isn't the strongest out there at the time, but they had to draw a line somewhere or the 840av would have ended up costing 2x the price.

e.g.

You want DSP? Thunder IV

The Thunder IV cost an **obscene** amount of money in it's day. It also doesn't accelerate video capture or the audio component. Both those make the video capture in the 840av possible right off the blocks with no add-on cards.

AV inputs? Get a spigot AV or videovision or an avid setup (for which the 950 was the supported model)

You want high quality audio? Audiomedia II

Faster SCSI - atto IV or jackhammer

Want 72 pin ram (and a PPC)? Powerpro 80MHz w/ ram expansion

Ok, lets look at that list.

DSP, already there.

AV Inputs/Video processing, already there.

High Quality Audio, already there.

72-pin RAM, already there.

Oh, and you were posturing about the 040 upgrade for the 840av being rare? I don't expect those PowerPro cards are exactly 2-a-penny either...

So what do I need all these NuBus slots for again? Maybe you want to empty your wallet into Radius Rockets (admittedly very cool, but still...) or buying 6 SCSI arrays and the cards to run them, or maybe you need 7 monitors.

And most importantly you don't have to choose which cards to leave out - you can have it all!

Even *if* you added a Thunder IV (I'm lucky enough to have one in my 840av, which I class as verging on the excessive, but still...), and Wide SCSI (which I also have) that leaves a spare slot and I can do everything your so called 'ultimate' system can do. I even have room to add a Spigot PowerAV to boost the video capture capability even further.

Plus you keep AUX compatibility.

The only thing bad I'd say about the q950 is the noise - which can surely be fixed.

Now, see A/UX is a server OS, for the greater part. This is something that the 950 is good at. Well, it is and it isn't. At the end of the day it's a Mac, it was made to be used. No Mac of that era ever even approached actually being a decent server in the grander scheme of things. The Amiga had a better 68k UNIX anyway, and they released theirs first.

Also the noise is important, this is a workstation, deigned to be worked at/near. I don't expect to go deaf in the process.

PS: I would like to see some benchmarks - maybe macbench your 840av's & let us know?

My 840av is a sentient life form and I would never agree to this kind of torture under the Geneva Convention...

I don't need to benchmark it, the reason it's better has nothing to do with some arbitrary figures. Benchmarks mean jack squat when it comes to usability and real speed. I can suck in PAL video and dump it to a disc array without much effort and that's all I care about. I also know It's quiet and doesn't weigh enough to kill me when I move it. You can take your ultimate 950, and the fork truck you use to move it around, and drive off in to the sunset.

 

[kreats]

Well it's like getting a motherboard with everything integrated. Chances are you wouldn't have chosen the parts that are built in and you don't even have the option of removing them - nothing inbuilt in the 840av is best in its class once upgrade cards are regarded.

IMO a Q840av can't compete with an avid or videovision setup regardless of what it is, and today a thunder IV just isn't expensive. Mostly, cost isn't an issue today.

Powerpro cards are reasonably common - more common than any upgrade you'd ever find for an 840av. You'd probably have to pay a few hundred bucks for any such upgrade - and btw no need to be rude.

I know it isn't what you want to hear, but (emotional attachment aside) an upgraded 800/650 is probably the best "ultimate" all rounder of the last generation macs. Personally, I'd rather the 2 extra slots and comprehensive compatibility of the 950/900.

 

[equill]

I'm with kreats in my preference for the 950, especially. Video has no fascination for me, on any machine at any time. Sound I edit on far more capable machines than 68K. So my preference is utilitarian: number of NuBus slots and drive bays; a PPC upgrade path; a PSU to support those; Rocket, WGS and A/UX capability, ease of access (albeit that the fastenings for the side panel are fussy); and a nice, warm, comfortable, heavy presence. Mine aren't noisy, but if they were, I should simply replace their fans with a quieter model. To me, the 950 is the ultimate 68K Mac. To paraphrase whomever it was, that may be but my appraisal, but it's the one that I am sticking to.

de

 

[Bunsen]

Damn, I want a 950 now

 

[Maconthemove]

Yeah, kicking my self for giving away two 950's.

 

[Unknown_K]

I never pass up a working 950, which is how I have 5.

 

[Quadraman]

I think we can agree that the 840AV and 660AV models were created for a specific purpose and no other Quadra can beat them at that but for more general use one of the other Quadras might be a better choice.

 

[p.amadeus]

in terms of out of the box stock functionality sure, but with upgrades a 950 can more than likely outperform a 840av in all respects

 

[Quadraman]

A IIfx with 6 radius rockets would be pretty fast, too.

 

[Unknown_K]

And useless without video or networking.

 

[kreats]

Some links:

"Macintosh: SCSI Data Transfer Rates"

http://docs.info.apple.com/article.html?artnum=12315

"Developer Notes: All Hardware Products"

http://developer.apple.com/documentation/Hardware/hardware2.html

Apparently the 840av has a tweaked nubus design - it'd be interesting to see if this made a difference with any nubus performance. AFAIK cards have to be specifically designed to support nubus90 to realise any benefit.

 

[Bunsen]

Hmm, that's interesting. No listing for the 2300, and none for the beige G3. From memory, the latter is a mere 5MB/s.

In fact no listing for any of the PPC Powerbooks.

 

[equill]

Just as interesting, in a wry sort of fashion, is the frequent (Developer) reference to 'five NuBus expansion slots with NuBus ’90 features and space for oversized NuBus cards' (my emphasis) in the 900/950.

What useful card, if any, ever took advantage of NuBus 90?

de

 

[kreats]

From the Q840av notes RE improved nubus:

"Improved NuBus interface. Both models use the Macintosh Universal NuBus Interface (MUNI) for accessory cards. This interface supports block transfers and data bursts to and from the main processor bus. MUNI capability is optional in the Macintosh AV Centris 660."

"The Macintosh Universal NuBus Interface (MUNI) is a CMOS chip in a 208-pin package."

"The MUNI version of NuBus supports the full range of NuBus master/slave transactions with single or block moves, including dumps and runs in which the main processor is master and NuBus is slave supports faster data transfer rates to and from the CPU bus supports NuBus90 data transfers between cards at a clock rate of 20 MHz provides First-in, First-out (FIFO) buffering of data between the CPU bus and accessory cards AV , the MUNI is mounted on the main circuit board; in the

In the Macintosh Quadra 840 AV Macintosh Centris 660 , it is on an optional NuBus adapter card. Details of the MUNI operation are given in NuBus Interface, later in this chapter."

"MUNI provides separate FIFO buffers for data on the CPU bus and on NuBus. These buffers can operate concurrently"

"All data transfers on NuBus are synchronized by a 10 MHz clock. An additional 20 MHz clock supports burst transfers in cards that conform to the NuBus90 specification. This permits faster data transfers than are possible with earlier NuBus designs."

Dunno if that helps.. there's a little bit more in the appendix about needing to alter the ROM of cards which support this improved nubus. Apparently nubus features (specifically block transfers) are laid out a bit clearer in the designing nubus cards book/document.

 

[Quadraman]

Was Nubus 90 used in the PPC Nubus machines?

 

[Unknown_K]

All Quadra era machines have some Nubus 90 features, but the 660AV and the 840AV are the ones that got most of them.

"Nubus '90 features - All Quadra computers have some Nubus '90 features. Traditionally Nubus has a throughput of 10MHz while Nubus '90 has a throughput of 20MHz."

from: http://www.angelfire.com/ca2/tech68k/quadra.html

"NuBus 90 NuBus 87 back compatible. avg throughput: ~30 MB/s (I&CS {Instrumentation & Control Systems} 07/92 v65 n7 p23(2)); burst mode: 20 MHz 70 MB/s (Noah Price). I/O bottleneck removed with Quadra 660av and 840av (MacWeek 08/02/93). 6" card standard was enforced in newer machines. Replaced by PCI."

from: http://members.aol.com/BruceG6069/mac-ibm-info.html

 

[trag]

A IIfx with 6 radius rockets would be pretty fast, too.

And useless without video or networking.

You'd have networking; you'd have 230 Kb/s LocalTalk.

 

[trag]

From the Q840av notes RE improved nubus:

"All data transfers on NuBus are synchronized by a 10 MHz clock. An additional 20 MHz clock supports burst transfers in cards that conform to the NuBus90 specification. This permits faster data transfers than are possible with earlier NuBus designs."

It should be noted that Apple's implementation of NuBus 90 only allowed for 20 MHz transfers from NuBus card to NuBus card. All transactions to or from the host machine (the Macintosh) was at 10 MHz. I don't know when you'd ever see a NuBus transaction directly from one NuBus card to another, except maybe in some of the Audio Media suites of cards, or perhaps between Radius Rockets.

 

[Unknown_K]

There were early video accelerators on their own Nubus card that sped up quickdraw over the Nubus to the Video card (I have ones made by rasterops) that would have benefitted from the 2x speed card to card. Those cards were bus mastering and had their own RAM (up to 16MB for RAM cache or Gworld).

Another possibility would be for video capture cards to send data directly to the SCSI card.

Most multi card setups just had cables from one card to the other to get away from hogging the slow Nubus.