VOGONS


Reply 21 of 23, by rasz_pl

User metadata
Rank l33t
Rank
l33t
Hoping wrote on 2024-10-24, 16:44:

What about something like this?
Re: Packard bell PB450 repair / mods / upgrade

That was my $2-4 proposal in second post of this thread 😀

https://github.com/raszpl/FIC-486-GAC-2-Cache-Module for AT&T Globalyst
https://github.com/raszpl/386RC-16 memory board
https://github.com/raszpl/440BX Reference Design adapted to Kicad
https://github.com/raszpl/Zenith_ZBIOS MFM-300 Monitor

Reply 22 of 23, by Omarkoman

User metadata
Rank Member
Rank
Member
rasz_pl wrote on 2024-10-24, 14:04:

yes

thank you, then its super simple and Im happy to give it a crack.

Reply 23 of 23, by byte_76

User metadata
Rank Member
Rank
Member

I would like to have additional voltage adjustment options for my two 486 boards, GA-5486AL and GA-486AM/s.

The first board has three voltage options which are 3V, 4V and 5V.
The second board has one jumper which allows auto selection between 3.3V / 5V and 4V.

I would like to be able to confiture voltages between 3.3V - 4V, (Eg. 3.45V, 3.6V, 3.8V) because that would potentially allow me to reach stable overclocks of my AM5x86 P75 and Cyrix 5x86 100GP on these two boards without applying excessive voltage.

In the case of the AM5x86 P75, it runs at 160MHz with 4V but it could probably manage that with 3.45V or 3.6V. (It isn't stable at 3.3V)
The Cyrix OC's to 120MHz at 3.3V and is mostly stable but Quake bench crashes. If I could just add a little extra voltage, like 3.45V, it would probably be enough to stabilise the system.

What options do I have in terms of voltage regulators or adapters? (Or any other methods?)