Hello.
I have acquired this motherboard that seems to come from a M300-30.
The cpu soldered on is a 486sx 25.
There is an empty socket for a cpu but I have no idea what cpu I could place.
487SX co-processer? https://www.ardent-tool.com/Olivetti/Docs/ser … tems1/cap36.pdf
snufkin wrote on 2022-05-03, 11:59:487SX co-processer? https://www.ardent-tool.com/Olivetti/Docs/ser … tems1/cap36.pdf
Cool.
Reading this shows that I can place an overdrive cpu on it. (Not sure though)
What kind of overdrive processor I need?
I heard that some sockets require the ODP or ODPR,
Can I use the dx4 100 overdrive?
apparently it can be modded to accept ordinary DX2s
https://youtu.be/aK6iLC4s4Ts?t=242 "IBM PS/1 DX4! upgrade with more Cache and RAM. And I got the ancient virus.Boot.AntiExe" Epictronics
https://github.com/raszpl/sigrok-disk FM/MFM/RLL decoder
https://github.com/raszpl/FIC-486-GAC-2-Cache-Module (AT&T Globalyst)
https://github.com/raszpl/386RC-16 ram board
https://github.com/raszpl/440BX Reference Design adapted to Kicad
Damn, that board is enormous, how proprietary would you like your motherboard to be? Yes.
rasz_pl wrote on 2022-05-04, 01:54:apparently it can be modded to accept ordinary DX2s
https://youtu.be/aK6iLC4s4Ts?t=242 "IBM PS/1 DX4! upgrade with more Cache and RAM. And I got the ancient virus.Boot.AntiExe" Epictronics
Awesome video - why get a normal 486 VLB motherboard plus chip if you can have a dude with a funny accent explain to you how to cheat an SX-25 with a soldering rod?
You should so try that, even if it means to learn how to solder. But don't ruin the board, chances are someone will desperately look for it to fix some weird Italian desktop.
Video says one can't alter the FSB frequency - does that apply here as well? No point messing with that quartz?
Else it should be possible to run it at 33 or even 40.
Then, a DX-2 would be the last word, since, as explained in the video, later CPUs need 3.x volt and the old boards only have 5 V.
Or, you'd need an overdrive CPU or an adapter socket with voltage regulation. Both exist in the room next to the unicorn storage.
AFAIK, the socket originally was meant to retrofit a 487 mathematical co-processor, for whatever weird reason instead of buying a DX right away. That would have turned that SX25 into a DX25, which still is a slug. The FPU would make little difference in most games.
But if the DX2 conversion works, it should make an ok DOOM machine?
Have fun!
I like jumpers.
