Here is the type of voltage adapter im talking about incase you are wondering.

From time to time you can find them on eBay... But they are not cheap - from 15 up to 30€.

kixs wrote:

From time to time you can find them on eBay... But they are not cheap - from 15 up to 30€.

OK, ill just keep an eye out for future.
Otherwise ill try and find an overdrive CPU

I wonder how these would cost to manufacture today. I'm pretty sure it would be useful to many people !

Dirt cheap to manufacture, if you place an order in a magnitude of thousands / tens of thousands of units. Otherwise it wouldn't be profitable at all as you'd have to actually reverse engineer everything, design a PCB, make new sockets and all.

You would be surprised how easy these parts can actually be obtained in china.
Just look at all the products for Commodore64 that are still made.
Anyway, lets assume the sockets are not made anymore, there are probably plenty of dead 486 mobos out there that a socket could be removed from and installed on a board such as this. Does not cost much to get some PCB's made.

Keep an eye out on CPUworld for an Intel DX4 overdrive. Prices are often half that of eBay. You can also look for 486 upgrade modules. They often contain an Am5x86-133, which can be replaced with an Intel DX4, if that is what you are after.

feipoa wrote:

Keep an eye out on CPUworld for an Intel DX4 overdrive. Prices are often half that of eBay. You can also look for 486 upgrade modules. They often contain an Am5x86-133, which can be replaced with an Intel DX4, if that is what you are after.

OK thats cool, i did not know you could buy them there.

You click on the forum, then navigate to "For Sale/Trade (collectable items)". Check past listings for unsold items and wait for more listings to come up.

You also have "Wanted/Buy" sub-forum. Maybe someone has them for sale. But usually they sell untested stuff as users there are mostly after collecting/displaying chips and not actively using.

thats cool, ill do that and check for listings. I should really get a collection myself mind you.

Old thread worth bumping.
Anyone know if there are any replicas made of these regulators?
Or have a schematic? It looks simple enough to make as a weekend project.
Probably just a linear 3.3 and a bunch of caps & diods.
These are very useful!
Thanks

Edit: probably an LT1587 inside that heatsink.
If it's simple enough it should be possible to make on a proto board?

epictronics wrote on 2020-04-22, 21:53:

Old thread worth bumping. Anyone know if there are any replicas made of these regulators? Or have a schematic? It looks simple e […]
Show full quote

Old thread worth bumping.
Anyone know if there are any replicas made of these regulators?
Or have a schematic? It looks simple enough to make as a weekend project.
Probably just a linear 3.3 and a bunch of caps & diods.
These are very useful!
Thanks

Edit: probably an LT1587 inside that heatsink.
If it's simple enough it should be possible to make on a proto board?

PM feipoa . If anyone has a schematic it would be him 😀

Keep an eye on this thread, Custom interposer module for TI486SXL2-66 PGA168 to PGA132 - HELP! . Perhaps if/when someone finishes that PGA-132 to PGA-168 interposer board, they will feel pumped up to do a simple PGA-168 to PGA-168 voltage adapter.

If you're going to go to the trouble of reproducing a VRM, I would add a couple of enhancements.
At the very least it should have a trimpot for overclocking, and a jumper to set 487SX mode for motherboards that only have an overdrive socket (OEM systems had SX chips soldered to the board). Some but not all VRMs had this.

You might also want to consider adding some advanced stuff, like a jumper to set Ti486SXL pinout, and maybe solder pads in the centre for adding a Cyrix 87XLC FPU. FPU support for Cyrix 486S would be nice too.

But what I think would really bereally cool is if you could put a programmable IC on there so that you could set CPU registers for Cyrix 5x86 CPUs. Then you wouldn't have to run the configuration program during boot. Ideally you'd configure the chip from DOS, and of course there should be a way to reset things if you screw it all up.

nzoomed wrote on 2017-08-06, 23:25:

Does anyone know where you can find these? […]
Show full quote

Does anyone know where you can find these?

Ive got a OPTI 495SLC motherboard and would love to install a DX4-100 CPU in it if possible.
I have seen there these sockets that plug into the motherboard with a voltage regulator on board to cut the 5V down to 3.3V so you can install a later CPU that runs on 3.3V.

Only other option is to find a 486 overdrive cpu that is 100Mhz. These dont look easy to find.

Any other ideas?

Your waisting your time and money. There is only about a 10% performance increase going from 486dx2-66 to a 100mhz CPU.
If you really want a performance boost then get an 83mhz Pentium Overdrive CPU.

The 486dx2-66 uses a 5v socket and 33mhz bus.
So if you are using a 486-33mhz you are good. You just need to swap CPU’s

For Most DOS and Win3x games the 486dx2-66 is good enough.
But if you want to play Modern DOS games then get the Pentium.
The 100mhz 486 CPU will not provide you with enough performance boost over the 66mhz CPU in playing Modern DOS games.

Actually, For a Really good DOS gaming computer you want a Pentium CPU 75mhz - 233mhz.
16mb ram or more.
CF card as a harddrive
2mb or better video card.
Good sound card
4x CDROM drive or faster

Which is actually the best and least expensive option for a DOS gaming computer.

Intel486dx33 wrote on 2020-04-23, 15:10:

Your waisting your time and money. There is only about a 10% performance increase going from 486dx2-66 to a 100mhz CPU. If you r […]
Show full quote

nzoomed wrote on 2017-08-06, 23:25:

Does anyone know where you can find these? […]
Show full quote

Does anyone know where you can find these?

Ive got a OPTI 495SLC motherboard and would love to install a DX4-100 CPU in it if possible.
I have seen there these sockets that plug into the motherboard with a voltage regulator on board to cut the 5V down to 3.3V so you can install a later CPU that runs on 3.3V.

Only other option is to find a 486 overdrive cpu that is 100Mhz. These dont look easy to find.

Any other ideas?

Your waisting your time and money. There is only about a 10% performance increase going from 486dx2-66 to a 100mhz CPU.
If you really want a performance boost then get an 83mhz Pentium Overdrive CPU.

The 486dx2-66 uses a 5v socket and 33mhz bus.
So if you are using a 486-33mhz you are good. You just need to swap CPU’s

For Most DOS and Win3x games the 486dx2-66 is good enough.
But if you want to play Modern DOS games then get the Pentium.
The 100mhz 486 CPU will not provide you with enough performance boost over the 66mhz CPU in playing Modern DOS games.

Actually, For a Really good DOS gaming computer you want a Pentium CPU 75mhz - 233mhz.
16mb ram or more.
CF card as a harddrive
2mb or better video card.
Good sound card
4x CDROM drive or faster

Which is actually the best and least expensive option for a DOS gaming computer.

AM5x86-PR75 - DX5@133MHz, easily overclockable to 150MHz, frequently 160MHz.

You sort of notice the difference then...

dionb wrote on 2020-04-23, 15:30:

Intel486dx33 wrote on 2020-04-23, 15:10:

Your waisting your time and money. There is only about a 10% performance increase going from 486dx2-66 to a 100mhz CPU. If you r […]
Show full quote

nzoomed wrote on 2017-08-06, 23:25:

Does anyone know where you can find these? […]
Show full quote

Does anyone know where you can find these?

Ive got a OPTI 495SLC motherboard and would love to install a DX4-100 CPU in it if possible.
I have seen there these sockets that plug into the motherboard with a voltage regulator on board to cut the 5V down to 3.3V so you can install a later CPU that runs on 3.3V.

Only other option is to find a 486 overdrive cpu that is 100Mhz. These dont look easy to find.

Any other ideas?

Your waisting your time and money. There is only about a 10% performance increase going from 486dx2-66 to a 100mhz CPU.
If you really want a performance boost then get an 83mhz Pentium Overdrive CPU.

The 486dx2-66 uses a 5v socket and 33mhz bus.
So if you are using a 486-33mhz you are good. You just need to swap CPU’s

For Most DOS and Win3x games the 486dx2-66 is good enough.
But if you want to play Modern DOS games then get the Pentium.
The 100mhz 486 CPU will not provide you with enough performance boost over the 66mhz CPU in playing Modern DOS games.

Actually, For a Really good DOS gaming computer you want a Pentium CPU 75mhz - 233mhz.
16mb ram or more.
CF card as a harddrive
2mb or better video card.
Good sound card
4x CDROM drive or faster

Which is actually the best and least expensive option for a DOS gaming computer.

AM5x86-PR75 - DX5@133MHz, easily overclockable to 150MHz, frequently 160MHz.

You sort of notice the difference then...

I think Win95 performs best on a Pentium CPU.
And the 5x86 can’t play MP3’s very well.

The Pentium is just a smarter choice.
Play games and music the way it was intended to be heard. No lag.

Going from a DX/2-66 to a DX/4-100 should give you a lot more than a 10% boost especially if you're using an Intel DX4.
POD83 is borderline useless as a 486 upgrade, because the 5V systems that actually need it can't run it at full speed. Not to mention, it's only really fast at floating point operations. For things that need integer performance, AMD and Cyrix are better alternatives.