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Let's try this :) Just ordered.

You are right, no harm in trying :) Will finish recapping with OS-CON first, just in case I'm stupid again !

Hi all... back after a long time. I started replacing my tantalum caps by OS-CON on my 660AV motherboard. Except I was not cautious enough, and broke a leg of the MC88920... bummer. :( It's really broken close to the package and of course, this is pin 8... UTSource lists some variants as new...

OOOps, I even said 68040 instead of 68030... :) I really needed that break !

So, yes clearly, there is a ROM socket, but on your photo you can also easily spot the 2 ROM chips on the right side of the 68040. Now I'd be very honest, I only tested until I got a chime and cursor, not sure if it would go further. I've taken a few days off, so can not test on my IISi right...

Thanks for the info ! We do learn so much. In my case, I DID realise I could change the trimmer on the fly :) I used it a lot to try and guess the upper limit that I could reach. Spicy is a fantastic tool. I have started with my 660AV, but I have other machines to play with, just need more...

Yes, I got it as a sales for about 180€ ($180 USD). Basic, but pretty cheap, and perfect for all the 65x or 68k machines which are all below 100 MHz.

OK, so I need to try that, I had seen the video from @JDW about it. And also watch the quality of the PSU caps. They all "looked" fine with no leaks, but this does not mean they are still at their nominal values. I know partially put the Mac back in the case so I could plug the HD more easily...

mmmhhh There is no HDI-45 on the 660AV. ! :) As for the lower ESR caps, that is never a bad idea I guess. I will take a break soon, but will do that when back (along with finishing my 2 SE Reloaded boards and other projects.

Nope... that would have been to clever :( In fact the machine was working but nearly all caps had leaked, so I did not think twice and replaced all of them with Tantalum ones. In fact, you can see the before and after recapping throughout the thread. I will try to further analyse the rails, as...

So @Kay K.M.Mods it kind of works. Lowering further the clock, I could have some overclocking. I could reach 16.5 MHz (so 33 MHz CPU, which is normally within specs), the Mac would boot, but plugging any device will make it hang immediately (even a keyboard). Using 15.0 MHz (30 MHz, only 5...

Excellent, let me try that. In my previous experiment, you can see the lowest frequency I got was 17.42 MHz, but maybe I'm not luck with the 33 MHz rated CPU. So let's try the resistor to explore slightly lower frequencies :)

Hey no worry, I'm here to explore things ! ):

Yes, they are definitely close, and the Apple developer notes helps as well. I was just looking for clarifications around the clock divider as you may have seen in the Spicy O'Clock thread. A few differences on the clock generation topic. Nothing major, but I'm unsure if it affects my...

Oh if there are sources for reliable 68040RC40 :)

Hi @Kay K.M.Mods @Zane Kaminski :) (and all others of course... @JDW ) So I had a bit more time to play and investigate today. First, I did solder some pins to J36 which makes to more convenient to measure see picture. BTW my wiring was not completely right but that's not the point. I also...

Zane, It's good to have the 840AV Bomarc schematics for reference, do we know if the 660AV one do exist ? I'm looking specifically for things around the clock generation for the Spicy O'clock thread... I guess they are similar, just checking.

Have a good night, it's about time ! :)

Looking at the oscillator documentation here : https://www.farnell.com/datasheets/57482.pdf Apple really brought all relevant signals to the J36 connector so we can easily have a replaceable oscillator. That is crazy. @Kay K.M.Mods Spicy O'Clock AV special edition ? :)