I picked up a Macintosh LC III the other day it didn't chime initially at power on but with a bit of coaxing it fired up chimed and tried to load the OS although the SCSI drive was whining and grinding away.
So I thought I would see what upgrades I could do starting with BlueSCSI. This was an easy fix and once running also allowed Wi-Fi through the BlueSCSI device. The BlueSCSI didn't need powering through the SCSI power to floppy power connector as there was enough power in the SCSI cable.
I haven't finished but alongside the BlueSCSI I added a 16MB RAM stick to add to the onboard 4MB giving 20MB. One ice feature I like on this is the VRAM SIMM slot for upgrading the video ram. I got hold of a 256KB stick to add to that slot. It's a little bit shorter than a normal 72pin RAM slot.
Finally I need to do the following. This 68030 runs at 25MHz and there is an easy 0 OHM SMD resistor swap (basically jumpers) that puts it at 33 MHz. The CPU chip runs a little hot so will add a heatsink. Replacement battery is on order too. Lastly adding in a 68882 FPU to complete. Oh and it needs a clean :)
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Macintosh LC III TLC
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Icky
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Macintosh LC III TLC
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HigashiJun
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Re: Macintosh LC III TLC
Looks neat !
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stephen_usher
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Re: Macintosh LC III TLC
You need to replace those SMD caps ASAP before the cap juice eats the traces.
You’re very lucky that it’s not battery bombed!
You’re very lucky that it’s not battery bombed!
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
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rubber_jonnie
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Re: Macintosh LC III TLC
Nicely tricked out, but as @stephen_usher says, worth doing the SMD caps for sure.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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Badwolf
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Re: Macintosh LC III TLC
Very nice!
Time for a bath!
BW
Time for a bath!
BW
DFB1 Open source 50MHz 030 and TT-RAM accelerator for the Falcon
Smalliermouse ST-optimised USB mouse adapter based on SmallyMouse2
FrontBench The Frontier: Elite 2 intro as a benchmark
Smalliermouse ST-optimised USB mouse adapter based on SmallyMouse2
FrontBench The Frontier: Elite 2 intro as a benchmark
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Icky
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Re: Macintosh LC III TLC
@stephen_usher / @rubber_jonnie - yep that's the plan when I get time to replace those caps. I did also notice power fluctuations from the PSU which was partly the cause of the initial non-power up. I am going to recap the PSU as well. And Stephen yes, am lucking the battery didn't leak.
Should be a nice little desktop once done. I quite like the neatness of the design and layout @HigashiJun. I sort of compare this to a TT but better built :)
Am super impressed with the BlueSCSI board its really neat on this Mac and has a lot of tooling and the fact if provides a SCSI Ethernet / Wi-Fi setup is awesome.
Lastly LC III was built more for education and there was an LC III+ variant which had the speed bump. The more consumer version of the LC III is the Performa 450.
@Badwolf - it definitely needs one.
I did have a fleeting thought of putting a slot behind the LC III badge for the SD card but then I am totally against bodging cases. Even if removing the badge and having the slot there and being able to put the badge back over to hide it in the future. Still couldn't bring myself to go down that route.
Should be a nice little desktop once done. I quite like the neatness of the design and layout @HigashiJun. I sort of compare this to a TT but better built :)
Am super impressed with the BlueSCSI board its really neat on this Mac and has a lot of tooling and the fact if provides a SCSI Ethernet / Wi-Fi setup is awesome.
Lastly LC III was built more for education and there was an LC III+ variant which had the speed bump. The more consumer version of the LC III is the Performa 450.
@Badwolf - it definitely needs one.
I did have a fleeting thought of putting a slot behind the LC III badge for the SD card but then I am totally against bodging cases. Even if removing the badge and having the slot there and being able to put the badge back over to hide it in the future. Still couldn't bring myself to go down that route.
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stephen_usher
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Re: Macintosh LC III TLC
I'm sure someone could port EmuTOS to it. ;-)
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
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rubber_jonnie
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- Posts: 14728
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Re: Macintosh LC III TLC
I had a Mac LC475 BITD which I really liked, it was a great little machine, and I had an LCII, both recovered from a school along with relevant CRTs. This was probably over 25 years ago!!!
I'm kinda disappointed I got rid of the LC475 as it would be a fun little machine now and I could really spice it up with stuff like BlueSCSI, but alas It's gone. Also they seem to command a high price on eBay...
I do have my Mac Classic though and dropped a BlueSCSI in that and it works great. BlueSCSI also works great in my Archimedes A5000, they are bloody brilliant :)
I'm kinda disappointed I got rid of the LC475 as it would be a fun little machine now and I could really spice it up with stuff like BlueSCSI, but alas It's gone. Also they seem to command a high price on eBay...
I do have my Mac Classic though and dropped a BlueSCSI in that and it works great. BlueSCSI also works great in my Archimedes A5000, they are bloody brilliant :)
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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stephen_usher
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Re: Macintosh LC III TLC
The LC and LCII are both highly crippled machines. They have a 68030 on a 16 bit bus for a start. They're also highly resistant to overclocking. If you change the crystals for higher speed ones somehow the chipset detects it and compensates, bringing the CPU clock back to the stock speed.rubber_jonnie wrote: 16 Apr 2026 10:52 I had a Mac LC475 BITD which I really liked, it was a great little machine, and I had an LCII, both recovered from a school along with relevant CRTs. This was probably over 25 years ago!!!
I'm kinda disappointed I got rid of the LC475 as it would be a fun little machine now and I could really spice it up with stuff like BlueSCSI, but alas It's gone. Also they seem to command a high price on eBay...
I do have my Mac Classic though and dropped a BlueSCSI in that and it works great. BlueSCSI also works great in my Archimedes A5000, they are bloody brilliant :)
The LC475 is generally thought of as the sweet spot for the Low Cost series machines.
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
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rubber_jonnie
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- Posts: 14728
- Joined: 17 Aug 2017 19:40
- Location: Essex
Re: Macintosh LC III TLC
Indeed they are, but the LCII I had was free so I can't complain :)stephen_usher wrote: 16 Apr 2026 11:17
The LC and LCII are both highly crippled machines. They have a 68030 on a 16 bit bus for a start. They're also highly resistant to overclocking. If you change the crystals for higher speed ones somehow the chipset detects it and compensates, bringing the CPU clock back to the stock speed.
I got this free from the same place as the LCII but it was clearly superior and half decent to use. IIRC the guy told me that the LC475 was used as a server and the LCII's all connected to it.stephen_usher wrote: 16 Apr 2026 11:17 The LC475 is generally thought of as the sweet spot for the Low Cost series machines.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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