rmay635703 wrote on 2022-03-14, 14:06:

I’ve often thought a little universal kit should exist for converting/ upgrading linear motherboards to switched replacements

Time for BW's scary 3.something Volt strap proposal, get a bridge rectifier, snip off the inputs and put the negative output to 5V and positive output to 3.3V pin. That gives you two diodes in series dropping 1.4V from the 5V line, in a parallel pair, so it does 2x as much current as rated.... but most of the time it will end up 0.1 to 0.3 higher than regulated so it will tend to blow up first, closely followed by the regulator.... so you'd only wanna do that if you fiddled the 5V down to 4.8 and vreg output was 3.5, so it would come in to relieve the regulator when the voltage started to droop. Orrr, if you got a 5A rated bridge regulator to do it with, so it was basically getting all the amps through that. However, depending on 5V fluctuations your core voltage would be a bit random between 3.4 and 3.8V. It's dissipating all the extra too so gotta sink it. This idea sponsored by the committee for abuse of vintage hardware, it's kind of a "don't do this unless you know what you're doing, but if you know what you're doing you've probably got a saner idea."

Though as I think I said to someone else tryna put excessive CPU in a socket 5.... First look up the part number of your linear regulator and order 10 spares....

We need a powerleap project for the community.

Apparently, there are not only ways to multiplier throttle vs temperature there are also ways to move the cache to the interposer and ignore the mobo cache. We could be seriously upgrading some of these old socket 5 setups with a interposer. 512k-2mb of 4ns cache, voltages from 1v-4v clean multi stage power conversion, etc.

I did lash up a possible design for a carrier board for a Murata switch mode adjustable supply module that may (or may not) fit in the space available (may need a small motherboard mod to supply a Ground level to the module). Don't think it's actually been tested though:
Re: Gigabyte GA-586HX (Rev. 1.53)

Majestyk did connect up the module directly and that bit seemed to work ok.

I rather see a Buffalo memco style memory upgrade that fits into your cpu socket setup but for 286, 486 and pentium instead of just 386

snufkin wrote on 2022-03-14, 22:07:

I did lash up a possible design for a carrier board for a Murata switch mode adjustable supply module that may (or may not) fit in the space available (may need a small motherboard mod to supply a Ground level to the module). Don't think it's actually been tested though:
Re: Gigabyte GA-586HX (Rev. 1.53)

Majestyk did connect up the module directly and that bit seemed to work ok.

Oh there’s that thread I was looking for. That’s a cool project. I think if someone made and sold those they could help a lot of people’s mobos.

I just added it to the vrm roundup thread. Thx

Another thread: Re: Wacky experiments: running a K6-2 on Socket 5 without an interposer

rmay635703 wrote on 2022-03-14, 23:44:

I rather see a Buffalo memco style memory upgrade that fits into your cpu socket setup but for 286, 486 and pentium instead of just 386

There seems to be a lot of stock of Quad Flat Package fast 486 available, Intel DX4-100 and AMD 5x86-133, whacking those on an interposer with cache and 64MB of RAM and regulator so they run in anything that takes a 5V DX33 would be great.

There might be enough PLCC or QFP 486SLC and related critters to do the same for 386.

Guess you'd have to do a socket for the Socket5/7 version, or just secure a large amount of those K6-2+ at a decent price and solder those on. Possibly you'd want up to 256MB on those.

BitWrangler wrote on 2022-03-15, 01:47:

There seems to be a lot of stock of Quad Flat Package fast 486 available, Intel DX4-100 and AMD 5x86-133, whacking those on an i […]
Show full quote

rmay635703 wrote on 2022-03-14, 23:44:

I rather see a Buffalo memco style memory upgrade that fits into your cpu socket setup but for 286, 486 and pentium instead of just 386

There seems to be a lot of stock of Quad Flat Package fast 486 available, Intel DX4-100 and AMD 5x86-133, whacking those on an interposer with cache and 64MB of RAM and regulator so they run in anything that takes a 5V DX33 would be great.

There might be enough PLCC or QFP 486SLC and related critters to do the same for 386.

Guess you'd have to do a socket for the Socket5/7 version, or just secure a large amount of those K6-2+ at a decent price and solder those on. Possibly you'd want up to 256MB on those.

What are we talking about? Pics?

Repo Man11 wrote on 2022-03-15, 01:03:

Another thread: Re: Wacky experiments: running a K6-2 on Socket 5 without an interposer

vrm module project thread roundup, share ideas, make new designs

Thanks!

Sphere478 wrote on 2022-03-15, 02:13:

What are we talking about? Pics?

I’m bugging the one guy who bought this???
For photos of his example

https://yahoo.aleado.com/lot?auctionID=b357325415

I thought it was a 386 upgrade but appears to be 486 related, in effect it’s similar to a cpu upgrade interposer but instead of a cpu upgrade you get a means of installing memory.

https://web.archive.org/web/20061231182931/ht … 95/0095cpu.html

The buffalo solution sadly locates the ram above 16mb and requires drivers, would be better to locate “at the top” of whatever ram is there (contiguous ) And no driver.

I have systems that either are purposely crippled or have extremely limited memory upgrade solutions, making it an all around upgrade memory + cpu device would be neat but latching memory would be hard enough.

Oh that’s cool.

I didn’t realize that it was possible to put ram there. I thought it had to be attached to the north bridge

rmay635703 wrote on 2022-03-15, 15:09:

I’m bugging the one guy who bought this??? For photos of his example […]
Show full quote

Sphere478 wrote on 2022-03-15, 02:13:

What are we talking about? Pics?

I’m bugging the one guy who bought this???
For photos of his example

https://yahoo.aleado.com/lot?auctionID=b357325415

I thought it was a 386 upgrade but appears to be 486 related, in effect it’s similar to a cpu upgrade interposer but instead of a cpu upgrade you get a means of installing memory.

https://web.archive.org/web/20061231182931/ht … 95/0095cpu.html

The buffalo solution sadly locates the ram above 16mb and requires drivers, would be better to locate “at the top” of whatever ram is there (contiguous ) And no driver.

I have systems that either are purposely crippled or have extremely limited memory upgrade solutions, making it an all around upgrade memory + cpu device would be neat but latching memory would be hard enough.

53C57E9D-4C7E-46B7-BB74-4192F62A5C27.jpeg

Never even knew something like this even existed.
Learned something new again xD

Sphere478 wrote on 2022-03-15, 19:54:

Oh that’s cool.

I didn’t realize that it was possible to put ram there. I thought it had to be attached to the north bridge

If you use cache as memory there is no technical reason you need a north bridge to interact but the dos memory size would need to clear and map the memory since the system would just ignore and not latch.

Since i have tested 3 Buffalo/Melco Upgrades, i can say that the memory expansion option does not work on 'western' PCs. It uses a different enable-method for the memory and puts the additional memory above 16m. The NEC-PC98 series does not use the A20-Gate to access XMS but a different method. It may be possible to modify DOS or DOW4GW to use the NEC-specific way to enable the memory.
As of now, the additional memory on the Melco/Buffalo upgrades is not usable in IBM PCs.

-Jonas