PowerBook 500 Series full 040 CPU swap

[croissantking]

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?

To source? Very difficult –

I found one on eBay after a lot of digging and persistence.

There are some reconditioned 68040FE33V chips on eBay and AliExpress, but 100% avoid those because even the non-fakes don't have an FPU according to Motorola's spec sheet. My chip ending in M is the same as the ones seen in the PowerBook 550c.


To swap over? It depends –

It's not a job for a beginner in SMD rework. For an experienced person, it's relatively easy to do, you just have to take a lot of care not to bend the pins while removing and cleaning up the donor chip. On the CPU card that's being reused, you also have to take great care to clean up the pads without lifting any.

On my first attempt, the CPU card worked, but then froze up after 5 minutes of runtime, and then it wouldn't reboot. I reflowed all the pins and it still didn't work, so I went back again and identified a couple of solder bridges. After cleaning those up, it now runs reliably. A microscope would have helped a lot – it's my next purchase.

 

[Phipli]

There are some reconditioned 68040FE33V chips on eBay and AliExpress, but 100% avoid those because even the non-fakes don't have an FPU according to Motorola's spec sheet. My chip ending in M is the same as the ones seen in the PowerBook 550c.

The "V" is also the wrong voltage isn't it?

 

[croissantking]

The "V" is also the wrong voltage isn't it?

Is that right? I wasn't aware.

 

[Phipli]

Is that right? I wasn't aware.

 

[croissantking]

@Phipli - that's good to know, they're doubly wrong for this project in that case.

 

[Powerbook27364]

To source? Very difficult –

I found one on eBay after a lot of digging and persistence.

There are some reconditioned 68040FE33V chips on eBay and AliExpress, but 100% avoid those because even the non-fakes don't have an FPU according to Motorola's spec sheet. My chip ending in M is the same as the ones seen in the PowerBook 550c.


To swap over? It depends –

It's not a job for a beginner in SMD rework. For an experienced person, it's relatively easy to do, you just have to take a lot of care not to bend the pins while removing and cleaning up the donor chip. On the CPU card that's being reused, you also have to take great care to clean up the pads without lifting any.

On my first attempt, the CPU card worked, but then froze up after 5 minutes of runtime, and then it wouldn't reboot. I reflowed all the pins and it still didn't work, so I went back again and identified a couple of solder bridges. After cleaning those up, it now runs reliably. A microscope would have helped a lot – it's my next purchase.

Thanks very much for the information. I will keep an eye out for one of the correct chips

 

[mg.man]

thinking positive thoughts!

And -- well done!! Way .

 

[MacUp72]

nice..was it done with a hot air station? new oscillator, yes, you could just buy three different ones and test how far it goes..

 

[croissantking]

nice..was it done with a hot air station? new oscillator, yes, you could just buy three different ones and test how far it goes..

Well, yes… but I have a certain method. I added some low-melt solder (42% tin/58% bismuth) all the way round and then only turned up the hot air station to about 200 degrees or so. More cleanup is required but it’s gentler on the chip.

 

[croissantking]

What will that FPU get ya?

Better performance in select applications that use the FPU. Based on my own usage I’ll probably never see any difference. That’s not why we do these things, of course

 

[3lectr1cPPC]

Based on my own usage I’ll probably never see any difference. That’s not why we do these things, of course

And that about sums up the hobby
"I just maxed the RAM in this thing. It feels the same as it did before, but I sure am happy about it!"

 

[Phipli]

And that about sums up the hobby
"I just maxed the RAM in this thing. It feels the same as it did before, but I sure am happy about it!"

I noticed the difference when I overclocked a C650 by 60% day before yesterday

 

[akator70]

I'm sure you all know this, but back in the day there was plenty of pro software that required a FPU. 3D, CAD, animation, statistics and analysis, scientific, I'm sure there's stuff I'm forgetting. A lot of the software wouldn't run without a FPU and using a soft FPU (when that worked) was unbearably slow.

 

[Phipli]

I'm sure you all know this, but back in the day there was plenty of pro software that required a FPU. 3D, CAD, animation, statistics and analysis, scientific, I'm sure there's stuff I'm forgetting. A lot of the software wouldn't run without a FPU and using a soft FPU (when that worked) was unbearably slow.

Audio software too. Even some games.

For some things SoftFPU and patience was enough, but some stuff really needed it.

 

[LaPorta]

I never realized how many tinkerers there were for these kinds of things. My goal has always been straight preservation: nothing more. Once I get a machine in fully functioning shape, that’s it, I’m done. It is intriguing to me how many of you do these things “just because.”

 

[Phipli]

I never realized how many tinkerers there were for these kinds of things. My goal has always been straight preservation: nothing more. Once I get a machine in fully functioning shape, that’s it, I’m done. It is intriguing to me how many of you do these things “just because.”

I've always enjoyed making changes I know I can reverse. I never drill a hole in something, but I'm more than happy to swap out components and make new parts.

For example my IIx has a custom hard disk bracket that holds two 3.5" disks, and my SE has a custom PCB that makes the disk activity light show the activity for the hard disk and SCSI2SD I fitted.

 

[LaPorta]

For example my IIx has a custom hard disk bracket that holds two 3.5" disks, and my SE has a custom PCB that makes the disk activity light show the activity for the hard disk and SCSI2SD I fitted.

Those sorts of things are really cool . Little usability enhancements.

 

[alectrona2988]

woa! i have a spare pb520 card i should try this on, i have a powerbook 520 and it's very slow by default (gee i wonder why). never knew these were in the same package!!

 

[Durosity]

This is pretty cool.. I’d love to do this with a 33Mhz chip for my 550c at some point!

 

[croissantking]

This is pretty cool.. I’d love to do this with a 33Mhz chip for my 550c at some point!

You definitely should!

I’m guessing this mod could be applied to the 190 and the Duo 280c.