LC/LCII Power Supply Replacements?
- Thread starter DracheMitch
- Start date
LazarusNine
Well-known member
Looking good! That’s a very clean design as well. Thanks for the regular updates. Can’t wait to see how this progresses.
I’m going to see if I can get a few more done before sending them off; in the hopes of getting a better deal on shipping. SE & SE/30 as well as whichever variant works with a IIvx (I’d have to go look that up; I think it’s the same one that works with a IIcx & IIci?)
I’m also waiting on some parts from China that shipped the slow route…
I’m also waiting on some parts from China that shipped the slow route…
LazarusNine
Well-known member
I think that’s right regarding the IIvx supply. Pretty sure it’s the same as the one that powers the Q700/IIcx/IIci, and a quick internet search appears to confirm that. I even swapped in a 7100 PSU into my Q700 when its PSU died. Prioritising the SE & SE30 + IIcx/ci/vx/Q700 designs seems sensible, given the popularity of the former and the broad capture of multiple machines in designing something for the latter. I am personally most keen on PSU replacements for the Q700/IIci + SE/30 in addition to your LC run, so take that anecdotal data for what it’s worth!
Also, those are what machines I have to test with: one SE; one SE/30 (full machine); one SE/30 logic board with battery damage; one LC; and one IIvx (just arrived).
The others - as of yet - probably don't need PSU replacement: a Gossamer G3; a grey G4 tower (I forget which rev - it's not the mirrored one); an iMac DV, and a 2010 Mac Pro.
BeigeBoxSC
New member
I just recapped the PSU in my Performa 400 and it was unsuccessful. I'm looking forward to seeing your new product!
Franklinstein
Well-known member
I think we have some other power supply threads in the various forums that cover a good bit of these topics, especially in the Hacks & Development section for building replacement devices. Good to see more progress though.
Essentially the following should interchange either directly or with minimum effort:
*Mac 128k/512k/Plus
*Mac SE/SE/30
*Classic/Classic II
*LC 500 series up to LC575 and derivatives (though similar I don't think the 58x models interchange)
*LC/LCII/LCIII/LCIII+/LC475 and derivative models
*IIcx/IIci/IIvx/IIvi/P600/Q700/Q650/PM7100 (though the later models have higher wattage ratings they're downward-compatible with the older models)
*6-slot Mac IIs (same deal-later models may have higher wattage ratings but they're downward-compatible)
*Q800/Q840av/PM8100
*Q610/Q660av/PM6100/various Performas (later models may have higher wattage ratings)
*Q630/PM6200/6300 and derivatives up to but not including the Performa 6360 or other PCI-based models
*PMG3MT/B&W G3/Yikes! G4/AGP G4 all use basically standard ATX power supplies
*GE/DA/QS G4s all use the same special ADC ATX-style power supply though it's trivial to mod these to accept standard ATX if you're not using ADC.
There are others that should interchange (several of the PCI Power Macs such as the 8500 and 9500 for example) but I can't say for sure since they seemed to like changing the harnesses around between models in this era.
Essentially the following should interchange either directly or with minimum effort:
*Mac 128k/512k/Plus
*Mac SE/SE/30
*Classic/Classic II
*LC 500 series up to LC575 and derivatives (though similar I don't think the 58x models interchange)
*LC/LCII/LCIII/LCIII+/LC475 and derivative models
*IIcx/IIci/IIvx/IIvi/P600/Q700/Q650/PM7100 (though the later models have higher wattage ratings they're downward-compatible with the older models)
*6-slot Mac IIs (same deal-later models may have higher wattage ratings but they're downward-compatible)
*Q800/Q840av/PM8100
*Q610/Q660av/PM6100/various Performas (later models may have higher wattage ratings)
*Q630/PM6200/6300 and derivatives up to but not including the Performa 6360 or other PCI-based models
*PMG3MT/B&W G3/Yikes! G4/AGP G4 all use basically standard ATX power supplies
*GE/DA/QS G4s all use the same special ADC ATX-style power supply though it's trivial to mod these to accept standard ATX if you're not using ADC.
There are others that should interchange (several of the PCI Power Macs such as the 8500 and 9500 for example) but I can't say for sure since they seemed to like changing the harnesses around between models in this era.
ironborn65
Well-known member
Is this a dead thread? I'm planning to use an HD IDE PSU for a Performa 475. The lack of -5V means I’ll lose LocalTalk support — not a big deal, but not ideal either.
My main concern is the power requirements. An HD IDE PSU provides 2A on both +5V and +12V rails. Is that enough for a Performa 465? My setup includes an Ethernet card, 1 MB VRAM, 8 MB RAM, a BlueSCSI card, and I also intend to soft-overclock it
My main concern is the power requirements. An HD IDE PSU provides 2A on both +5V and +12V rails. Is that enough for a Performa 465? My setup includes an Ethernet card, 1 MB VRAM, 8 MB RAM, a BlueSCSI card, and I also intend to soft-overclock it
Fizzbinn
Well-known member
I believe the stock LC power supplies are between 3.25A and 4.75A for 5V so 2A might not be enough. They are 0.75A to 1A for 12V so 2A should be more than enough there.
There is the "POWER UP PIZZA" from CayMac, I built one recently, sourcing the Mean Well power supply modules from mouser. IRM-20-5 for 4A 5V & -5V and IRM-10-12 for 0.85A 12V, from mouser. You re-use some parts and the case from an existing LC power supplies.
I think the CayMac store is currently down for the operator's holiday, not sure when it might be back up, hopefully soon, they have some great stuff!
YouTube video on a slightly older revision of this:
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Fizzbinn
Well-known member
You also might want to take a look at this thread for another option:
Replacement Power Supply in Quadra 605
the power supply in my souped up Quadra 605 died, and i am too lazy to recap it. (Q605 is recapped with tantalum, HD replaced with SD card, pretty new VRAM, 128MB RAM, and a full 68040) Following knowledge from a thread on TinkerDifferent I searched out a MeanWell RPT-60A, a small power supply...
68kmla.org
cheesestraws
Well-known member
Is this one of the blocks with a molex on the end from say Amazon? if so - be aware that these are of... extremely variable quality, and I worked on one with @joshc that simply would not regulate properly under any kind of load. I'd be very careful with these.
There are loads of ways to generate -5 V if you want LocalTalk - I usually end up using an isolated DC/DC 5V-5V converter, which is overkill but I've got a tube full in the cupboard. They're easy to wire up and basically self-contained.
The meanwell RPT-60A is a decent option here if you don't mind doing a bit of crimping. It will fit inside the existing case and will provide you all three voltage rails with enough oomph to power a 475, at least from my experiments.
I would suggest being very cautions about community-designed power supply projects that take in mains at one end. They rarely seem to have things like proper separation and I would tend to consider them a fire risk. It is generally a better bet to get PSUs from reputable people who actually design PSUs and adapt the pinout on either end.
ironborn65
Well-known member
Yes, it’s the one with the black block and a Molex connector on the end. I read about it here in the forum, where someone mentioned using it.
I thought that without an HD and an accelerator, it would be sufficient. The Mean Well RPT-60A is definitely better — for what it worth, it’s also sold as a 'medical' device. Good enough if I ever decide to drive a heart pump from the 475. It’s more solid, more powerful, and just a little pricier.
I've rebuilt a couple of PSUs for IICI and IICX, rebuilding the soft power, so crimping is not a big deal.
I thought that without an HD and an accelerator, it would be sufficient. The Mean Well RPT-60A is definitely better — for what it worth, it’s also sold as a 'medical' device. Good enough if I ever decide to drive a heart pump from the 475. It’s more solid, more powerful, and just a little pricier.
I've rebuilt a couple of PSUs for IICI and IICX, rebuilding the soft power, so crimping is not a big deal.
cheesestraws
Well-known member
Yeah, the problem turns out to be with those that there's multiple different internal versions, all of which look identical externally, and some are relatively decent and some are crap. If you get one of the decent ones it's - unsurprisingly - decent - but you're taking a gamble.
ah yes the rare and somewhat scary 'medical' end of the retrocomputing hobby. I might keep that a long way from me ;-)
killvore
Well-known member
+1 for the Meanwell RPT-60A. It fits inside the original LC PSU housing so unless you open up the PSU itself it looks like the original part. It provides +5V, -5V, and +12V and is intended for medical grade equipment so it seems pretty reliable. Not much trouble getting it mounted in there, just some basic soldering.
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ironborn65
Well-known member
I've ordered two of them .... it all makes sense to me, thanks
killvore
Well-known member
Make sure the black heatsink does not touch the metal enclosure for the original PSU, since it can short out and ruin it. It has some protective black paint on it, but it can chip off. I covered the meanwell with some black insulation I got from inside an XServe, and taped up the reverse side of the PSU with kapton, so there's a double layer of electrical insulation. No heat issues!
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