• Hello, Guest! Welcome back, and be sure to check out this post for more info about the recent service interruption and migration.

What OS to put on a Quadra 840AV?

Nathan_A

Well-known member
Howdy,

So, I'm going to be repurposing my 8100/100 in my collection, and replacing it in my display setup with a Quadra 840AV. I'll move my Radius VideoVision, SuperMac Thunder/24 + DSP, and DigiDesign AudioMedia II from the 8100 to the 840.

So the multimedia workstation display will be:
  • Quadra 840AV (fastest 68k)
  • PowerTower Pro 250 (fastest non-MP clone)
  • Quad G5 (fastest PowerPC)
I'm running 9.1 on the PTPro and 10.5 on the G5.

I'm wondering what makes the most sense to run on the 840AV? My current thought is to put 7.6.1 on it. That way there's a non-Platinum UI machine in the lineup, compatibility with era appropriate 68k software, etc.

Does the 68040 hold up alright on 7.6.1? I've previously only ever put 7.1 on 68k machines.
 

NJRoadfan

Well-known member
How much RAM in the 840AV? Also does it have flash storage? I've found System 7.5 and up pokey on 68k machines, but they can easily run it with plenty of RAM and nice fast storage. The stock hard drive and 8MB of RAM isn't going to cut it. I remember cringing seeing a brand new Performa 630 absolutely crawl and grind away while booting 7.5.

The 840AV doesn't offer backwards compatible features like 24-bit addressing, so there is no real reason to stick with older system releases. The only holdup may be drivers for the NuBus cards. Some did break with later OSes.
 

Nathan_A

Well-known member
I'll probably max out the RAM and put a modern 7200 RPM UltraSCSI drive in it. I have a few NOS Seagate drives I picked up as a lot of 4 recently for $20 a piece. The drive itself should definitely be able to outperform the SCSI bus it's attached to, and should feel pretty snappy. I put one in my SE/30 and it really gave it a nice boost. Basically it feels like the drive is waiting on the computer more than the computer waiting for the drive.
 

Johnnya101

Well-known member
I put 7.5.3 on my IIfx which has maxed ram and an scsi2sd. It seems to be okay. Some instability on some programs, but I think it's some cards I have installed. I would try 7.5.3, maybe dual boot with 7.1.1?
 

Nathan_A

Well-known member
Welp, I've already got 7.6.1 install images on my "Bootstrap" Jaz disk, so maybe I'll start there and see how it goes getting it all up and running tonight.
 

jeremywork

Well-known member
On the 840AV I find 8.1 very smooth and responsive, but if you only need the features of 7.x it only gets faster. I tend to keep multiple system folders on my machines though.
 

joshc

Well-known member
Does the 68040 hold up alright on 7.6.1?
Yeah, you just get a lot of extra fluff with 7.6.1 that you may or may not need. For the most part, you can add the functionality that 7.5/7.6 provided in 7.1 by installing various shareware apps/utilities. 7.6.1 is the most convenient but you end up with extra bulk in terms of control panels and extensions, but it should run fine on a 40mhz 040. Make sure you install enough RAM in that system too, the system memory usage does creep up quite a lot from 7.1 to 7.5 to 7.6 and to 8.1.

If I'm doing System 7 on a 030 or slower 040, I'd go for 7.1. With a 40mhz 040, you can get away more easily with 7.5, 7.6 or 8.1.
 

beachycove

Well-known member
Anything with a 68030 or 68040 is going to run 7.5.x perfectly well, though often only if the fluff (e.g., the animated AppleGuide) is turned off. Most of this fluff is entirely unnecessary.

‘PlainJane’ 7.5 is also stable on 68k hardware, and is nice and compact, whereas on PPC it is prone to crashing, but a cut down 7.5.x installation in my experience runs just as well as 7.5 on 68k machines, despite the fact that the installation is so much larger. Just cut the fluff away.
 

Nathan_A

Well-known member
The machine has 64 MB RAM it looks like. It turns out I don't think I have any 32 MB SIMMs, only 64 MB ones. Before I pop the motherboard and replace the SIMMs in vein, does anyone know if the Quadra 840AV will take 64 MB SIMMs to top out the memory at 256 MB?

The usual suspects about old Mac specs online say, "No.", but I've had those be wrong about so many things that I figure the community here probably knows the answer.
 

MrFahrenheit

Well-known member
The machine has 64 MB RAM it looks like. It turns out I don't think I have any 32 MB SIMMs, only 64 MB ones. Before I pop the motherboard and replace the SIMMs in vein, does anyone know if the Quadra 840AV will take 64 MB SIMMs to top out the memory at 256 MB?

The usual suspects about old Mac specs online say, "No.", but I've had those be wrong about so many things that I figure the community here probably knows the answer.

If you send me your 840av I’ll check it for you. Unfortunately, I would not be able to send it back once I confirm. ;)
 

Nathan_A

Well-known member
If you send me your 840av I’ll check it for you. Unfortunately, I would not be able to send it back once I confirm. ;)
:) I had to acetone "weld" almost all those little tabs that hold the front panel on one side. Those brittle little bastards snapped during shipping from Japan.

I'm hesitant to so much as move the thing. All these Quadra 800 style cases are the worst when it comes to durability, and it doesn't help that you basically have to dismantle the entire thing to do trivial things like add RAM & VRAM.

Side note: the machine came with a fresh install of 8.0-J on it, and I'm actually surprised how snappy everything feels even with its stock 250 MB HDD. It feels zippier than my 7100/80 that's running OS 8.1 when doing basic file browsing and fiddling with Control Panels. I'm sure the 7100/80 crushes it in optimized raw compute tasks, but that 40 MHz 68040 is no slouch.
 

Nathan_A

Well-known member

Running NetBSD is apparently underrated.
But, I won't be able to use any of my awesome Nubus cards then. 🙂

That said, I run Linux as my primary work OS on both my desktop and laptop, and I have a whole 90's esoteria stack in my home office museum: AU/X, NeXTSTEP, IRIX, Solaris, HP/UX, and the odd man out... BeOS.
 

MrFahrenheit

Well-known member

The way in which the 840AV deals with its memory (DRAM) differs from the other machines of its generation (Quadra 700, 800, 950) in that 4, 8, 16, or 32 MB 72-pin 60ns SIMMs may be installed up to 128 MB and sizes can be mixed. However, the Quadra 840AV does not support 1 MB, 2 MB, or 64 MB SIMMs. The 840AV and 660AV are the first Macintosh computers to operate in 32-bit mode at all times, and cannot be toggled back to 24-bit mode, which may be useful for using early Nubus cards that conform to the 24-bit addressing.
 

ArmorAlley

Well-known member
I always have a couple of volumes on my systems and I include the earliest and latest (within reason - System 7.5.3 on a Plus or SE is not to my liking, so I use System 7.1 instead).
I would install System 7.1.1 as your main driver if performance is what you are after.
You might try Mac OS 7.6.1 to see how it is. This version of the OS is spoken highly of by other members here.
I would have Mac OS 8.1 on another volume to give you access to HFS+ volumes.
For System 7.1.1, I would create a 48MB RAM drive and leave 16MB for the system and apps. 48MB should be more than enough for a system folder trimmed of stuff you don't need. Restart with the RAM disk as the system disk and you have a much more responsive system.
A flash-based HD (like the SCSI2SD and friends) should also do the trick.
For Mac OS 8.1, 32MB RAM is nice for the system & apps and leaves 32MB for a RAM-disk. It is still workable.
 
Top