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Everyone’s been talking about /AS. I think it’s the same signal as /LAS but generated independently. Like one is a repeat of the other. I don’t really understand why you’d have that, but I have confirmed an SE/30 board works fine either way (with UE7 pin 6 going to either /LAS or /AS).

In your revised schematics, and on Rev04 of the Reloaded board, UE7 pin 6 goes to AS* (UI6 pin 19, UI8 pin 47, UJ11 pin 27, RP7 pin 1). On an Apple board, UE7 pin 6 goes to LAS* (UI6 pin 3, UK8 pin J2, RP8 pin 15, PDS pin 89). I don't understand the discrepancy.

Reading through a bit, they had issues with instability and then discovered that the CPU was only rated to 16MHz. Definitely an accelerator built on the cheap. Still fascinating though.

Not sure if interesting but this summer I restored my PC built around an Athlon XP-M 2500+ CPU. It's actually the same PC I built back in 2003 and I've kept it all this time - although it has evolved from original spec. The Asus A7N8X Deluxe 2.0 I've now got in there is the fourth board that's...

I may need to take this comment back. Reading into it a bit, the cache is quite important as it would alleviate the wait states imposed by running the CPU asynchronously. I actually have a feeling that an accelerator like Sonnet Allegro SE/30 would provide only a minimal improvement in performance.

If you think you might be up to the task of designing such a circuit I’d be interested in working with you on it.

Also, https://web.archive.org/web/20210423175417/https://mac68k.info/forums/thread.jspa?threadID=277

I don’t yet have a logic analyser - sorry. This has been discussed before, I just found: https://68kmla.org/bb/index.php?threads/se-30-overclock-is-it-possible.5186/post-58845

No-go on that. It does, if I feed the bodge wire to the PDS slot C16M it starts. I found some info about this Sonnet card that clock doubles the SE/30 on Everymac.com. Looks like they have some logic to get things working. Would love to get my hands on one to reverse engineer.

I tried this and it 100% does not work. Just seeing a simasimac. The 25MHz chip in there should be good for 31MHz. Any ideas?

Pff, don’t need L2 cache. It makes barely any difference on my IIci. So I’m going to have to try this. Would it be as simple as desoldering the CLK pin of the 68030 and running a patch wire to the output pin of Y2? Or better to connect to the C32M output of UH7?

That would be an easy way to get a 2x speed boost. Seems a bit too good to be true because if you look at any of the 030 upgrades that fit in the CPU socket, they have a very large amount of logic.

Interesting, could this be pulled off with the CPU?

It looks great. No need to do any cleaning, maybe a quick blast with compressed air if you fancy. What I'd do is, remove the caps with the twist method (or whatever method you prefer), then use braid to clean up the pads. You could add fresh solder and then go over with braid again to get them...

Difficult to advise - we can’t see the board to see how relatively clean or filthy it is :) Maybe post a photo of the board? If relatively clean: don’t bother. If very dirty: I wouldn’t use any vinegar as it’s very corrosive and really only necessary for neutralising battery acid. An IPA bath...

Unlikely you killed more than just the ADB chip itself, although possible. i'd recommend installing PLCC sockets on your purple board. I did this on two of mine and it made things so much easier to debug.

Another idea is to run the oscillator outside of the board and then run a wire with the clock signal to the board. Regarding your bombed board, you say the problems began when you swapped the clock crystal with the one off your original board. Did you try putting back the bombed board's...

Let us know how it goes with the PSU. Looking at your purple Reloaded board I see the ADB chip is installed wrong. Guessing you caught and corrected that? Maybe post a pic of it as you had it when you'd finished assembling it.

@This Does Not Compute I too, would be interested in a video! You clearly put so much care into the whole process from start to finish, but were let down in certain key aspects by JLC. The poor packing and their 'hand-washing' is especially disappointing. I hope you can get your three boards...

Solved! https://68kmla.org/bb/index.php?threads/macintosh-se-30-logicboard-recreation-thread-revival.39485/post-512595