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PowerBook 500 Series full 040 CPU swap
Posted by: zigzagjoe on 2024-07-12 13:06:42
It’s legit. It came to me on an old piece of donor PCB, the FPU works and the marking on the chip doesn’t come off with IPA.
Interesting. I wonder what was being made 2016 or later that would have had a 68040 made in 2016 on it.
Posted by: croissantking on 2024-07-12 13:09:26
The mind boggles, does it not?
Posted by: jmacz on 2024-07-12 13:22:41
Yeah. I’m not sure what to make of it really. Are your chips 70ns?

Yeah, I believe so. Both my original memory chips as well as the donor chips had the same part numbers as yours did.
Posted by: Daniël on 2024-07-12 13:48:29
Interesting. I wonder what was being made 2016 or later that would have had a 68040 made in 2016 on it.
And on top of that, why it was scrapped this quickly, as you'd figure something put together with a '040 in 2016 would have probably been a drop-in replacement for vital legacy equipment that couldn't be modernized for whatever reason. 8 years or less is a fairly short lifespan for something like that, as far as I can tell!
Posted by: croissantking on 2024-07-12 13:50:43
Yeah, I believe so. Both my original memory chips as well as the donor chips had the same part numbers as yours did.
Well... I have a spare set of 60ns RAM chips that I'm going to swap out on one of my RAM cards. Just in case.
Posted by: jmacz on 2024-07-12 16:35:25
I ran another set of MacBench 3.0 and MacTestPro tests on the PB540c for a few hours. Just concluded and it's still holding up with the 40MHz overclocking and the same memory chips. FYI @croissantking
Posted by: croissantking on 2024-07-12 16:46:40
Could it be something else on my CPU card that's not holding up to the 40MHz bus, such as the large ASIC?
Posted by: jmacz on 2024-07-12 17:36:37
Not sure... here's a picture of my processor card:

IMG_8196.JPG

I've got Samsung branded chips in mine but with the same part numbers.
Posted by: croissantking on 2024-07-12 17:43:29
Not sure... here's a picture of my processor card:

View attachment 75694

I've got Samsung branded chips in mine but with the same part numbers.
What about the chip on the underside?
Posted by: jmacz on 2024-07-12 18:40:36
Here's the underside:

IMG_8198.JPG
Posted by: croissantking on 2024-07-13 13:58:36
Thanks for the photos @jmacz - I’ll compare these against my 4 CPU cards as soon as I get a chance. The big ASIC on the underside does look identical to one of mine.
Posted by: croissantking on 2024-08-05 10:07:51
I obtained some more of these quad flat pack 040s rated for 33MHz.

In case anyone is interested in who has been making new devices with 68040 CPUs in the 21st Century, I did a Google search for ENP2011051 which was on a sticker on the back of one of the donor boards. It comes off a Honeywell LCNP4E Experion LCN interface. The card I found images of appears to be made in 2011.
Posted by: zigzagjoe on 2024-08-05 11:06:19
Aha, that makes sense. Manufacturing automation and process control, that stuff is knee deep in legacy tech. There's a certain amount of irony in a 68040 on a PCIE card.
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