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PowerBook 500 Series full 040 CPU swap
Posted by: croissantking on 2024-03-07 06:45:13 I've just obtained one of these chips. All indications are - particularly the film of dirt - that it's a genuine part. I'm going to swap it into one of my 68LC040 processor cards later and hopefully, gain an FPU. This will go in my PB 540c if successful. I'm dead curious as to what the donor PCB was. I haven't yet seen these chips used anywhere other than in the PowerBook 550c. I have a hunch it would have been something industrial rather than consumer oriented.
Posted by: jmacz on 2024-03-07 23:32:26 Ooh, interested to see how this turns out!
Posted by: Bolle on 2024-03-08 00:12:26 That looks really good. Did they just cut out part of the PCB around the chip? 😅 Mine at least came on an interposer that could be reused at some point. As mentioned in the other thread somewhere, the swap is going to work with standard 520/540 CPU cards. The 550 ROMs are not needed for the FPU to work.
Posted by: croissantking on 2024-03-08 02:19:19 That looks really good. Did they just cut out part of the PCB around the chip? 😅 They did! Curious that there are no passive components on the back.
Posted by: History_SE30_Dude on 2024-03-10 20:53:16 Very cool, I was thinking about this as well. Along with possibly increasing the onboard RAM
Posted by: croissantking on 2024-03-11 05:35:51 Very cool, I was thinking about this as well. Along with possibly increasing the onboard RAM I saw someone claiming to have done this on a Japanese website. If it’s possible, it would be similar to @max1zzz ’s LCIII mod where you use flying wires to pick up the additional RAS signals. I think it would be tough to say the least, given the very small amount of working area.
Posted by: Phipli on 2024-03-11 05:37:07 Just need to fit a 68060 and make the ROM patches needed to get it going now 😉
Posted by: MacUp72 on 2024-03-11 23:33:38 Just need to fit a 68060 and make the ROM patches needed to get it going now 😉 now thats an idea.. the 060 is somewhat similar to a Pentium, also has a power saving option..has someone done that sucessfully, is there even a QFP one? but rare and not cheap🤟
Posted by: Phipli on 2024-03-12 01:35:30 now thats an idea.. the 060 is somewhat similar to a Pentium, also has a power saving option..has someone done that sucessfully, is there even a QFP one? but rare and not cheap🤟 It wouldn't work without hardware and ROM mods sadly 🙂
Posted by: Daniël on 2024-03-12 02:00:51 That looks really good. Did they just cut out part of the PCB around the chip? 😅 Not the first time I've seen IC salvagers from China and such take this approach. Honestly, I prefer it over desoldering, because they have some truly dodgy ways of doing that, like holding PCBs over hot flames and just slapping the board against a surface 'til they fall off 😬
Posted by: croissantking on 2024-03-12 09:37:19 The new chip is on. I’m going for a croissant break and I’ll be back to test shortly.
Posted by: croissantking on 2024-03-12 10:02:41 Pic of donor PCB remnant attached. ‘AS25’ has been revealed below the CPU.
Posted by: mg.man on 2024-03-12 11:50:51 The new chip is on. I’m going for a croissant break and I’ll be back to test shortly. View attachment 71039 🤞thinking positive thoughts!
Posted by: LaPorta on 2024-03-12 11:58:38 Ooh, let's see how it goes!
Posted by: croissantking on 2024-03-12 15:58:25 We're in business! @Bolle was correct in that the FPU is detected with the stock ROM. First boot: Comparison screenshots:
Posted by: 3lectr1cPPC on 2024-03-12 16:01:12 So then... PowerBook 530c? I mean, it's not quite a 550c due to the clock speed. I think the name fits.
Posted by: croissantking on 2024-03-12 16:04:20 So then... PowerBook 530c? I mean, it's not quite a 550c due to the clock speed. I think the name fits. Ha! It will be when I swap out the oscillator. 33Mhz, and if that works I'll try for 40. 530c will do for tonight.
Posted by: Powerbook27364 on 2024-03-12 16:19:51 Ooh this looks like a fun project for my 540c. How difficult was it to source and swap over the chips? Did anything cause any problems during the process?
Posted by: Phipli on 2024-03-12 16:22:33 We're in business! @Bolle was correct in that the FPU is detected with the stock ROM. First boot: View attachment 71053 Comparison screenshots: View attachment 71054 View attachment 71055 View attachment 71056 Absolutely awesome, but I suggest using a slightly older version of System Info 🤣 . This one is baselines on the 6100, before this they were baselines on the Quadra 700 which would give you more compatible scores 🙂
Posted by: LaPorta on 2024-03-12 16:22:59 What will that FPU get ya?
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