croissantking's conquests

[croissantking]

So to kick off this new thread, I've had a bit of luck on a 820-3330-B logic board (for a mid-2012 MacBook Pro 15") that I bought on eBay for £22. It was advertised as 'a faulty motherboard that doesnt appear to be powering on', so I thought I'd have a go at repairing it – with the intention of replacing the faulty board in my early 2011 MBP with its dead AMD graphics chip.

I installed it in the machine and not only does it boot, it works perfectly.

 

[Snial]

Cool!

 

[croissantking]

It is, you’d think a computer shop would be able to diagnose a failed board correctly, but there we are. Unless it’s an intermittent failure… but I’ll soon know. For now I’m enjoying it; currently installing macOS Catalina on it which is the last official version supported.

One thing I’m curious about - I’ve been able to install the RAM modules from my 2011 MBP, which are rated at 1333MHz, even though the 2012 board takes 1666MHz modules. It works fine… is the RAM being overclocked, or is the board running a slower FSB? I suspect the latter as it does report them as being 1333MHz modules.

 

[jmacz]

Hmm that’s cool! I have a similar MBP, near that time frame, first owner, and it died. This reminds me to open it up and try to figure out what’s going on. Only issue is I don’t think I have a battery or a power adapter for it now.

 

[croissantking]

Hmm that’s cool! I have a similar MBP, near that time frame, first owner, and it died. This reminds me to open it up and try to figure out what’s going on. Only issue is I don’t think I have a battery or a power adapter for it now.

The good thing is the batteries aren't glued in on those unibody machines, although I'm not sure how easy it would be to fabricate/obtain a replacement. Amazingly, my original battery from 2011 is still working really well. The power adapters are extremely annoying in that the cord always frays around where the captive magsafe lead leaves the housing of the charger. I've changed a few of those with knockoff cables which has worked well but they are infuriatingly hard to open up.

 

[VMSZealot]

Dead easy to replace the batteries - and I've done it on my my (now sold) 2013 MacBook Pro and my 2011 MacBook Air (which I still have). I always want a reputable brand, so here's a choice of two.

Newer may be better than new, but they don't do the latest computers.
iFixIt will even do batteries for the latest Apple Silicon machines.

Follow that link to battery nirvana! I've used both suppliers at various times, depending on stock etc.

 

[croissantking]

That’s great if they’re still making those batteries. I assumed the unibody MBPs would be getting to the point now where the only alternative would be a DIY battery rebuild, and my concern was that those battery packs don’t look like they’d have regular cells internally.

 

[VMSZealot]

Nope. Definitely no need to DIY. It’s amazing how old a Mac laptop needs to be before DIY becomes necessary. And when it is that old the batteries tend to be fairly easy to rebuild anyway.

 

[croissantking]

Another homemade 32MB RAM card built for a PowerBook 500 series.

 

[MacUp72]

wow, that looks clean, nice..does the ram now work properly?

 

[croissantking]

wow, that looks clean, nice..does the ram now work properly?

Sure does.

 

[croissantking]

I have a full 040 chip on order, a genuine one, so I’ll be swapping that onto the CPU card next.

 

[croissantking]

I picked up an 840AV today, a non-runner (thanks to @Adriana). They also threw a second motherboard in with the deal, and some accessories.



Both motherboards have had significant cap leakage, but the spare motherboard is in better shape:



The cap damage isn’t too terrible:



It cleans up like this with IPA:



It’s an earlier board with a ROM SIMM:



The board inside the case is a later one with a green PCB, and loaded with RAM and VRAM:



It’s had a battery leak:



The caps have done a tremendous and shocking amount of damage, I’m not sure I can save this one. Many of the fine pinned ASICs look like this:



There’s also two SCSI hard drives and a 24x SCSI CD-ROM drive (must be a pull from a very late 604e machine?), condition unknown.



I have a feeling its going to be a long road ahead, but I’m excited to get started. My plan is to try to get the brown motherboard working first as it’s definitely the one in better shape. I need to test the PSU as well.

 

[demik]

Another homemade 32MB RAM card built for a PowerBook 500 series.

View attachment 70394

Ho nice, happy that you managed to make it work

 

[joshc]

I picked up an 840AV today, a non-runner (thanks to @Adriana).

If you got them for £50, that was a steal! If I was in a different position (house move upcoming, maybe) I would’ve grabbed them… even though my Wombat that lives inside a IIci case is just as fast.

Good luck with reviving it.

 

[MacUp72]

I have a full 040 chip on order, a genuine one, so I’ll be swapping that onto the CPU card next.

a 68040 in the 540, like this guy here?

Ask Hackaday: Calling All 68k Experts

This is a tale of old CPUs, intensive SMD rework, and things that should work but don’t. Released in 1994, Apple’s Powerbook 500 series of laptop computers were the top of the line. The…

hackaday.com

oh, wow, you should do a new thread here about that adventure..

 

[Bolle]

I have a full 040 chip on order, a genuine one, so I’ll be swapping that onto the CPU card next.

Curious if it's going to be a real one or not.
I can tell swapping a full 040 onto a CPU board from a 520/540 does indeed work just fine, the 550 ROMs are not needed for the FPU to do its thing.

 

[MacUp72]

I wonder how difficult it is to de- and resolder the cpu onto the daughter board and what minimal equipment you would need..

 

[croissantking]

I wonder how difficult it is to de- and resolder the cpu onto the daughter board and what minimal equipment you would need..


View attachment 70491

I’ve successfully moved a 68030 from one PowerBook 165 daughtercard to another. The biggest difficulty is that the pads can lift.

 

[Phipli]

It’s an earlier board with a ROM SIMM:

That is really special. I've never seen an 840 with ROM. That opens up some really interesting projects for you.