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Daystar Turbo 040 for SE/30 - overclocked from factory?
- Thread starter s_pupp
- Start date
Good to know. Many thanks!
Doom is not really playable with the 50MHz 68030 in my SE/30 (now equipped with zigzagjoe's color LCD), and so I plan to put this long-shelved Turbo 040 to work. I recall Doom being only just-about playable on my long-gone Performa 475 with its 25MHz 68LC040, so I'm hopeful for the SE/30's chances.
Doom is not really playable with the 50MHz 68030 in my SE/30 (now equipped with zigzagjoe's color LCD), and so I plan to put this long-shelved Turbo 040 to work. I recall Doom being only just-about playable on my long-gone Performa 475 with its 25MHz 68LC040, so I'm hopeful for the SE/30's chances.
Not to be a downer or anything, but yeah, don't expect much from Doom.... You won't really have a playable experience as Doom is horribly limited by the ~16mhz system bus, both access to the framebuffer and main memory is slow. While the Mac Doom port is a good port from the perspective of being a well-behaved and well-integrated Mac OS application, it has had no 68k specific performance optimization done. As you mentioned, it runs poorly even on Quadras which have extremely fast framebuffers and a much better RAM implementation.
This assertion is based on my personal SE/30 with a socketed Carrera @ 45mhz (+ cache), with an Interware GrandVimage 24-21s accelerated card, otherwise a reasonably fast machine with a fast framebuffer. Marathon however you will find runs quite a bit better and will be actually playable. Not fullscreen, mind, but it's doable without it being a microscopic screen that Doom requires. That case can run marathon playably with fps in mid 20s @ the small (half screen?) resolution. In doom that machine averages 12fps in demos with a tiny 160 width screen, low detail, doubled pixels.
Well the fact that Doom is unlikely to be much better with the 040 in the SE/30 takes away some of the disappointment of both my Turbo 040 cards apparently being nonfunctional. They both worked 13 years ago. The other has an MC68040RC40A with a 21.504MHz crystal.
The fan comes on with either card, but no video and no startup bong - except for chimes of death on one occasion out of 10 attempts.
I removed the video card, but same result.
I tried a different Twinspark adapter, but same result.
It continues to run just fine with the 50MHz 030 card.
Power supply is a Seasonic SSP-250SUB.
Logic board has been recapped with aluminum polymers.
RAM is 128MB.
The drive is a 2GB Transcend industrial CF card in a CF-IDE adapter connected to an Acard AEC-7720U IDE-SCSI adapter.
I'll try on a different SE/30 at some point. In the meantime, I'm very happy with the performance of the 50MHz 030 for the vast majority of my software.
The fan comes on with either card, but no video and no startup bong - except for chimes of death on one occasion out of 10 attempts.
I removed the video card, but same result.
I tried a different Twinspark adapter, but same result.
It continues to run just fine with the 50MHz 030 card.
Power supply is a Seasonic SSP-250SUB.
Logic board has been recapped with aluminum polymers.
RAM is 128MB.
The drive is a 2GB Transcend industrial CF card in a CF-IDE adapter connected to an Acard AEC-7720U IDE-SCSI adapter.
I'll try on a different SE/30 at some point. In the meantime, I'm very happy with the performance of the 50MHz 030 for the vast majority of my software.
Check your voltages - Seasonics in my experience tend to have a bit of a low 5v rail to begin with, and the stock harness if you've not upgraded it (see here) will result in even more voltage drop. Accelerators often develop issues if you're below 4.85v.
Very good point about the voltage. This morning's experiment showed that it is indeed playing a role.
This morning, I modified the cable, replacing each of the the 22ga 5V wires with two paralleled 18ga wires (to approximate 16ga).
With the Seasonic PSU:
4.9V at PSU
4.67V at external floppy port with stock cable
4.80V at external floppy port with upgraded cable
I tried a Sony PSU and Stratos PSU with the upgraded cable:
4.86 at external floppy port for Sony PSU
4.88 at external floppy port for Stratos PSU
The computer showed signs of life only with the Stratos PSU: The minimally overclocked (43MHz) Turbo 040 consistently gave a startup bong. There was no hard drive activity, however, and the screen remained black. There are no signs of life beyond a spinning fan with the stock 40MHz Turbo 040. Trying to reset the PRAM did not result in a second bong.
I plan to route the 5V lines to an adjustable external power supply to see if increasing the voltage closer to 5V makes a difference.
Adjusting the Sony PSU to output 5V at the external floppy connector made no difference: Boots normally with 50MHz 030, startup bong but no further activity with 43MHz 040, no activity at all with 40MHz 040. The 12V line read 18V at the fan; I'm thankful I have aluminum polymers rather than solid tantalums on the logic board.
Could be the adapter too. The twinspark adapter is not an appropriate adapter for daystar cards, it's a clone of the Diimo 030 adapter and anything else that works with it is more of a coincidence rather than by design. Probably testing the cards in an IIci would be a good first step.
I see. Too bad - at the moment, I have no access to a IIci. My 68k Macs are Plus, SE, and SE/30.
I’ve read of a bodge wire mod for the Twinspark that can sometimes enable the cache in a Daystar 030, but I don’t know if this is a safe mod for an 040.
I’ve tried two additional SE/30’s with the Stratos PSU. One gave a simasimac with the 040 cards. The other is a magic 8 ball - it either boots and runs normally, throws a sad mac, freezes during startup, bombs during startup (“Illegal instruction”), or displays horizontal lines.
At least I know that the 040 cards are not dead.
Good that there's signs of life at least. The issue with the Turbo040 is a bit more fundamental. As I recall it needs some additional manipulation/inversion of the system clock and possibly a few straps. Bolle would know the specifics.
I just tend to get irrationally irritated that the twinspark is still sold (at a grossly overinflated price) while also being misadvertised resulting in folks having issues
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