68kMLA Classic Interface
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| Garage Finds: Lisa / MacXL (+ Sony CRT) | |
| Posted by: nickpunt on 2025-05-14 12:37:36 Ah ok it is a 512k upgrade, probably why the ram chips are socketed. Impossible to find the data sheets on the ram chips unfortunately. Quoting you @Unknown_K from this thread in VCEF in 2018: I pulled the card out of my Tandy and it is a PBJ Inc MFB 1000 c 1985 with 2 rows of Mt1257-20 chips. Those are 256Kx1 so I have a 512KB upgrade (16 chips)? Just pulled out my other 128k and yeah the original looks different.  | |
| Posted by: nickpunt on 2025-05-14 12:41:19 @Unknown_K yep we've got the pentium PC that goes with it too! Haven't tested it tho. Too much stuff in there to test.  | |
Posted by: cheesestraws on 2025-05-14 13:39:53Impossible to find the data sheets on the ram chips unfortunately Pretty sure they're just 41257s with the '4' missing for some reason. There were certainly 512ks with NEC 41256s in, and I'm pretty sure at least one other manufacturer was used but I can't remember who. The difference between the 41257 and 41256 is, I believe, that the 257 is NMOS. The datasheets for both 41256s and 41257s are available. Just pulled out my other 128k and yeah the original looks different. In case you're unaware, these Micron 4264s are known for self-destructing for no particular reason, and replacements are getting harder to find. Might be worth keeping a handful of spares (preferably not self-destructing Micron spares; I think I replaced mine with NEC ones?) | |
Posted by: Unknown_K on 2025-05-14 13:47:03@Unknown_K yep we've got the pentium PC that goes with it too! Haven't tested it tho. Too much stuff in there to test.The OEM install CDs for that model are on archive.org if you need them. | |
| Posted by: nickpunt on 2025-05-14 14:28:30 Yikes thanks @cheesestraws, will check to see if it boots next time I'm with the machine. Looks like they're in abundant supply thankfully Thanks @Unknown_K just went to archive and grabbed it! I have to figure out what to do with this VAIO machine, it's a complete system w keyboard and monitor but I don't have the space right now so it's staying at a friends. | |
| Posted by: Unknown_K on 2025-05-14 17:15:46 I have just the computer snagged locally for free. | |
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