Is the Quadra 610 Quaddoubler supposed to work in an LC475?

d3jsp

6502
Does anyone know if the 605/610 quaddoubler will work in an LC475? Tried it on mine but it will not chime or boot. I thought the architecture of an LC475 is identical to the Quadra 605
 
Does anyone know if the 605/610 quaddoubler will work in an LC475? Tried it on mine but it will not chime or boot. I thought the architecture of an LC475 is identical to the Quadra 605
Yeah, it should work. The only difference is that the memory performance is a tiny bit better on the 605, but that wouldn't impact your upgrade. If you want to be absolutely sure, remove the little jumper next to the hard disk power connector on the logicboard and your 605 becomes a 475.

One question - is your 605 overclocked?

Edit - sorry, I see you have a 475. I got muddled. Same thing, just add the jumper to turn a 475 into a 605.
 
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Ahh got it! Unfortunately it still will not chime with the pin and showing up as a Quadra 605 with the original 25 MHZ CPU. I guess maybe the 68040 on the quaddoubler is dead? Can I replace it with another 68040 or LC040 chip?
 
Ahh got it! Unfortunately it still will not chime with the pin and showing up as a Quadra 605 with the original 25 MHZ CPU. I guess maybe the 68040 on the quaddoubler is dead? Can I replace it with another 68040 or LC040 chip?
You could swap the QuadDoubler's CPU into the LC's socket? To test it that is.
 
I can try! would that boot on a 475?
If it is an 040 with pins yes. The only ones that don't work properly are weird ones that you wouldn't expect in the QuadDoubler like the low voltage versions and the ones without a memory manager.

It should be a higher speed grade, but that only means you're running it way slower than it could go.

Let us know how it goes.
 
The CPU indeed does boot! running at 25mhz with a co-processor. That means something else on the quaddoubler is defective or just not compatible with the LC?
 
The CPU indeed does boot! running at 25mhz with a co-processor. That means something else on the quaddoubler is defective or just not compatible with the LC?
Possibly - I'd start by sharing high resolution, well lit, photos of the top and the bottom of the QuadDoubler. If possible natural light.
 
Attaching some full res pictures
 

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It doesn't look too bad @d3jsp so I'll leave it to others to point out anything they spot.

Can you solder? The next thing I'd try is clocking the LC down to 20MHz. This means if your QuadDoubler was designed for a 20MHz Centris 610 and by bad luck can't handle a 25MHz bus, it will start working.

If that is the case, there might be better ways to speed up your 475.
 
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