chillin
Well-known member
When we speak of storage bandwidth, here, we're almost always talking about the internal SCSI-1 bus. But every interface on a logic board has bandwidth. Using the SE/30 as an example, it has an external SCSI port, the internal and external floppy ports, two adb and serial ports, a PDS, 68-pin ROM slot, 8 30-pin RAM slots, the power connector and possibly a socketed processor.
While the bandwidth for the SE/30 internal SCSI-1 bus is known to be 5MB/s max (though I have heard fantastic stories about 6MB/s), I wonder what the bandwidth is for everything combined.
Why not design and make available a sisterboard/hat to not only increase system bandwidth, but also include all the things we want. Imagine a board that is slightly smaller than the motherboard, and it connects from above directly with every single interface on the motherboard, busses, slots, and with a cable connects to and passes through all the external ports as well as the power port and passing a cable to the analog board, it just snaps in above and into the logic board, to everything. Also, imagine it not only provides a direct processing boost (say it runs... an 80MHz 68080), but also includes 512MB RAM, 16GB SSD, external dual SD Card reader slots, external 100BaseT network adapter, WiFi adapter, external USB2 port, external VGA, composite and HDMI ports, a replacement neck board and built-in GPU providing 16-bit grayscale to the internal display @1024x768, and can drive 3 external displays simultaneously.
Also imagine the overboard reaches a stalk off the top —actually the bottom of the upside-down sisterboard— that reaches through the PDS clearance in the chassis with a vertical NuBus slot that accepts a NuBus card with its usually outward-facing plate facing up at top.
But the most incredible feature of this überboard upgrade is that it seamlessly combines the throughput bandwidth of every possible interface on the logic board and makes that bandwidth available as storage bandwidth... storage faster than the OEM RAM slots, but the RAM only gets a little faster. I really don't know how it does this, perhaps borrowing ideas from ZFS, or maybe it somehow uses a blockchain, but it does it and does it well. Since the drives are no longer needed, they and the drive chassis can be removed, leaving room for uninterruptible power, or at least internal surge protection and battery backup.
While we're at it, let's imagine there's plenty of stock everywhere, and it's only 50 bucks new yet somehow appreciates rapidly, doubling its value every few months.
Now I ask you, what is wrong with this idea? Specifically, I refer to the idea of combining all interfaces and unifying them for maximum possible system bandwidth through use of an overboard, sisterboard or big hat. Ignore that we don't yet know how it is accomplished, but assume it is not physically or logically impossible.
If anyone happens to know all the maximum bandwidths of all the individual SE/30 logic board interfaces and can add them up and share that final tally, that'd be super. My guess is, altogether, it is just about, but not much above, a paradox-inducing 15MB/s.
Probably best just to design a modern replacement logic board from scratch specified to be hardware compatible with 68k Macs. But since software emulation is so good and processors so fast, it really doesn't absolutely need to be hardware compatible. It just needs to fit the footprint and ports slots and connect power and video to the analog board. But since off the shelf SBCs are already available and small enough, clusters too, and alternative display replacement options exist... this entire thought experiment is on a road to nowhere.
Well, back up a step... a new 68k board that takes advantage of modern advances and miniaturization (to cram in all the features), that is hw compatible with 68k Macs yet much faster, with lots of RAM and fast storage, that swapped in neatly... this would be kind of cool.
While the bandwidth for the SE/30 internal SCSI-1 bus is known to be 5MB/s max (though I have heard fantastic stories about 6MB/s), I wonder what the bandwidth is for everything combined.
Why not design and make available a sisterboard/hat to not only increase system bandwidth, but also include all the things we want. Imagine a board that is slightly smaller than the motherboard, and it connects from above directly with every single interface on the motherboard, busses, slots, and with a cable connects to and passes through all the external ports as well as the power port and passing a cable to the analog board, it just snaps in above and into the logic board, to everything. Also, imagine it not only provides a direct processing boost (say it runs... an 80MHz 68080), but also includes 512MB RAM, 16GB SSD, external dual SD Card reader slots, external 100BaseT network adapter, WiFi adapter, external USB2 port, external VGA, composite and HDMI ports, a replacement neck board and built-in GPU providing 16-bit grayscale to the internal display @1024x768, and can drive 3 external displays simultaneously.
Also imagine the overboard reaches a stalk off the top —actually the bottom of the upside-down sisterboard— that reaches through the PDS clearance in the chassis with a vertical NuBus slot that accepts a NuBus card with its usually outward-facing plate facing up at top.
But the most incredible feature of this überboard upgrade is that it seamlessly combines the throughput bandwidth of every possible interface on the logic board and makes that bandwidth available as storage bandwidth... storage faster than the OEM RAM slots, but the RAM only gets a little faster. I really don't know how it does this, perhaps borrowing ideas from ZFS, or maybe it somehow uses a blockchain, but it does it and does it well. Since the drives are no longer needed, they and the drive chassis can be removed, leaving room for uninterruptible power, or at least internal surge protection and battery backup.
While we're at it, let's imagine there's plenty of stock everywhere, and it's only 50 bucks new yet somehow appreciates rapidly, doubling its value every few months.
Now I ask you, what is wrong with this idea? Specifically, I refer to the idea of combining all interfaces and unifying them for maximum possible system bandwidth through use of an overboard, sisterboard or big hat. Ignore that we don't yet know how it is accomplished, but assume it is not physically or logically impossible.
If anyone happens to know all the maximum bandwidths of all the individual SE/30 logic board interfaces and can add them up and share that final tally, that'd be super. My guess is, altogether, it is just about, but not much above, a paradox-inducing 15MB/s.
Probably best just to design a modern replacement logic board from scratch specified to be hardware compatible with 68k Macs. But since software emulation is so good and processors so fast, it really doesn't absolutely need to be hardware compatible. It just needs to fit the footprint and ports slots and connect power and video to the analog board. But since off the shelf SBCs are already available and small enough, clusters too, and alternative display replacement options exist... this entire thought experiment is on a road to nowhere.
Well, back up a step... a new 68k board that takes advantage of modern advances and miniaturization (to cram in all the features), that is hw compatible with 68k Macs yet much faster, with lots of RAM and fast storage, that swapped in neatly... this would be kind of cool.
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