I bought a couple of these from a recycler some time ago, so I'm happy to experiment on one of them.

I really like these boards so it's exciting to think about making improvements to it and seeing how far it'll go. It's an Intel OEM board, the quality of which is excellent, and there is also a hidden surprise. It has 3.3v on the PCI slots! For an early Socket 7 motherboard, there is so much potential.

Kahenraz wrote on 2022-04-23, 03:00:

I bought a couple of these from a recycler some time ago, so I'm happy to experiment on one of them.

I really like these boards so it's exciting to think about making improvements to it and seeing how far it'll go. It's an Intel OEM board, the quality of which is excellent, and there is also a hidden surprise. It has 3.3v on the PCI slots! For an early Socket 7 motherboard, there is so much potential.

Oh that’s handy!

Alpha 11

-Various alignment and trace and location changes mainly on the jumpers. (not done)
-Updated Tillamook bf2 jumper to 3 pin to allow disabling of pull up due to cyrix using that pin for other functions.

debating reworking the pcb for 4 layers.

Ground plane,
vcc3 plane,
vcc2 plane,
5v plane.

but there are merits for not doing so also:

The more ground plane I keep between the pins the better,
the less vcc3 and 5v that's between the pins the better.

having whole planes between the pins of the whole socket just for a few connections here and there seems silly.

But alternately, I could replace the area between the pins on all layers with as much vss as I can and only route minimal connections through that area. but I'm kinda doing that now and it seems to be successful so far..

So like I said, torn on wether or not to do more than two layers… thoughts?

I don't know what any of that means (don't bother trying to explain it to me), but all of the big words you've used strikes confidence. Since I will probably be on of the first people to be testing this, I greatly appreciate the flattery.

Can anyone explain to me how these interposers are assembled? How is the top socket soldered to the bottom socket with the PCB in between? I've spent a lot of time examining various modules in my collection and could never figure it out. I have one that has broken pins that I've been wanting to repair.

Anonymous Coward wrote on 2022-04-30, 06:21:

Can anyone explain to me how these interposers are assembled? How is the top socket soldered to the bottom socket with the PCB in between? I've spent a lot of time examining various modules in my collection and could never figure it out. I have one that has broken pins that I've been wanting to repair.

catsay says they are soldered together, but I noticed on mine that you can push them together and it takes a small amount of force at first but for the last little bit it takes a significant amount of force. I pushed a few if mine together and am wondering if I can get them back apart 🤣

But you solder the lif to the board, then push the interstitial socket on. I had no illusions of trying to solder them together but a oven and solder paste in each hole may do it

wow, you've really been rocking on with this project of yours!

Well done!

CalamityLime wrote on 2022-05-02, 22:58:

wow, you've really been rocking on with this project of yours!

Well done!

Thanks 😀

Yeah, the voltage interposer is a particular challenge. The processor and motherboard interposer, I can see the finish line. Those projects are coming along very nicely. This one is gonna take a while 🤣. If anyone wants to help me co develop it lemme know 😀 people are of course welcome to make their own branch projects based on it also.

Spare time has been scarce lately. I’ll probably sit down and release another alpha stage here in the next week or two. Still a ways to go to prototype beta though.

Some news,

I gave converting the design to 4 layer a try and the benefits are undeniable.

Some more adjustments to do before next alpha, but soon. still a ways off From functional. Still evolving...

here is a sneak peak

I think I'm going to go with VSS as the upper and lower layer.

I may make some vss and vcc2 floods on other layers also but for the moment it seems:

VSS
5V
VCC3/VCC2
VSS

layers make a loooot of sense in general

-all the vss needs on both sides of the board and shielding is met by the surface layer
-5v has its own plane parallel to VSS. (I will likely shrink this plane and fill vss floods in many places on this plane for EMI reasons)
-vcc2/vcc3 also have their own plane but stay on their respective halves
-Implemented in a previous version, all of the unused holes are plated, but floating I noticed that other interposers did something similar. Perhaps if I remove the mask from these holes they may get enough solder mask in the hole to act as insulation to form a floating EMI shield

How many layers do you think the commercial products used? Maybe less because they don't have all of the fancy jumpers like in your design?

The OEM interposer I have at my disposal appears to have 2 layers. yeah, This design has more going on for sure.

Alpha 13

yeah, I'm liking this.

I'm probably going to flood some of the 5v layer with VSS also since there is zero point running it to the right, left and bottom.

Traditionally one puts power planes on the outside, But I have more room between pins on middle layers for traces, and putting VSS (ground) on outer layers can act as a faraday cage of sorts for all the power signals on the inner layers. (VSS is a power plane btw, being ground). point is, I have power planes on all layers. but the most stable one EMI wise is VSS. so put it on top and bottom. I'm working on these assumptions, 5v is probably really noisy. which is why I will shrink it away from un needed areas, vcc3 also is a little noisy so I may do some mitigation there also. vcc2 Shouldn't be all that bad. (it is what the board is designed to make after all. 😀 clean vcc2!)

Preview of the plane adjustments: this should help with EMI

I love all the pictures. Keep it up.

Some better views of the latest layer renders.

This is great! perfect power paths without sacrificing width, or having to stitch broken layers together with vias because of obstacles, and the noisy power signals are buried between vss layers as they pass between pins.

i don't like that I have to go from the inductors to the vcc2 layer using vias but not really a good way around that. More vias = less concern though

top vss

-

internal layer 5v/vss

-

internal layer vcc3/vcc2/vss

-

bottom vss

it may make sense to almost entirely replace vcc3 with vss and remove most of the vcc3 pads. as the interposer really only will use it for multiplier and mods which are low current and one or two pins would be sufficient. The motherboard supplies these pins with 3.3v.

So this type of thing might let me run an MMX on a non-MMX board? 😳

SteveC wrote on 2022-05-05, 23:18:

So this type of thing might let me run an MMX on a non-MMX board? 😳

It would indeed. Bios updates may also be required.

Alpha 14

lots of progress on this non functional Alpha.

-Buried all traces that go between the pins down where they have more breathing room under the surface. (seems oxymoronic 🤣)

- Added a few more components to be placed.

-Adjusted positions a tad.

-Put about as much VSS as possible between the pins on all layers.

Another feature that occurred to me:

I could add capacitors between vss and vcc3 to help with v I/O ripple from old capacitors on motherboards. Which may help with overclocking.

that do you think?

I believe it shows single digit voltage with two decimal places

might not be enough room...