It might be possible to trick the system into showing a small amount by installing a larger unsupported module.

Often installing something larger that isn’t supported will result in a smaller value.

Suggest single sided memory for tests.

Though using this method I believe you will end up installing a 256mb single sided and end up with 64mb

Which doesn’t accomplish your goal. So, sorry but that is all I got.

Past that, a custom module.

Not sure about CL2, but I am looking on eBay and found a 16MB PC100 stick. Most of them that are listed as 16MB are actually 128MB.

I'll post links/ parts numbers here in a minute.

PC100 CL3:
https://www.ebay.com/itm/125360702481?mkcid=1 … emis&media=COPY

Maybe this:
https://www.ebay.com/itm/404315931356?mkcid=1 … emis&media=COPY

One in this listing that says 16MB but can't read the chips:
https://www.ebay.com/itm/325753697484?mkcid=1 … emis&media=COPY

Says PC100 but guessing it is PC66.

SDRAM speeds are usually identifiable by the last numbers on the chips.

10=PC66
8=PC100
7=PC133

Looks like there were 16MB SODIMMs available as well. Maybe use an SODIMM to DIMM adapter if they exist.

Besides proprietary modules for “devices” and video cards you really aren’t going to find much
https://www.amatteroffax.com/e037-938.html

Ye olde 4mb, 8mb and 16mb sdram was lucky to be true pc66, moderately uncommon , occasionally 5 volt or 5 volt I/o tolerant and many times not Pc (aka Mac or ???)

Pc100 really launched alongside 32mb modules
Pc133 launched at 64mb

The few 16MB I have are PC100.

I can't see why only 16MB, because of motherboard limits?

16Mb is very small for PC133, you might find PC100 but even then its a bit small... Most of the sticks I remember were 64 and 128Mb.

Oh I have an idea, might be able to take a standard pc133 module and lift some of the address line legs on the chips. Might have to play with the spd using spd tool

Sphere478 wrote on 2023-08-03, 02:09:

Might have to play with the spd using spd tool

I think its can just get rid of the SPD chip.
Almost all SDRam-based systems (unbuffered and non-ECC) didn't give a damn about SPD, maybe except for motherboards manufactured by Intel.
The categorical presence of SPD began only on DDR memory.

Sphere478 wrote on 2023-08-03, 02:09:

Oh I have an idea, might be able to take a standard pc133 module and lift some of the address line legs on the chips. Might have to play with the spd using spd tool

That might actually work. The address lines will have to be pulled up or down, though ...

Nexxen wrote on 2023-08-03, 01:09:

The few 16MB I have are PC100.

I can't see why only 16MB, because of motherboard limits?

Scan them and post here for the benefit of the community.

I remember already in late 1997 that some 32mb dimms wouldn’t work in a VX system, (and virtually all 64mb didn’t work)

I don’t know of many mainstream companies in the pc100 era that made chips that would work as a 16mb dimm.

I’ve had thousands of dimms pass through my hands, strange thing is that in 16mb and smaller a swag says about 80% were STILL EDO and a not insignificant number were Mac or IBM specific.

16mb was obsolete by the pc100 era, 3rd party systems in that era still came with hybrid support so you could use up your old ram if you wanted but smaller dimms wasn’t really being produced in significant numbers by that point

ram

edit: too dark, I'll replace them soon.

shevalier wrote on 2023-08-03, 02:55:

maybe except for motherboards manufactured by Intel.

I know for a fact that all Intel 430TX OEM boards will boot without SPD chip with standard CL2, but if memory module has SPD and it's PC133, then it will boot with CL3.

So might be able to tape the SPD pin on a 32MB PC100 module (Which I have seen around) and get it to go CAS2 at 66. Also may be able to nobble it down to 16MB if wanted.

The smallest SDRAM dimm is 16MB for PC100 and the one at PC133 was only available in 32MB. In theory, you could depopulate the second rank and have a PC133 16MB?

Cheers,

pentiumspeed wrote on 2023-08-03, 22:45:

The smallest SDRAM dimm is 16MB for PC100 and the one at PC133 was only available in 32MB. In theory, you could depopulate the second rank and have a PC133 16MB?

Cheers,

Was it double sided? If so, yeah. Would probably work.

The only thing I can think of that would use 16Mb of PC100 is an industrial computer.

The Serpent Rider wrote on 2023-08-03, 16:29:

boards will boot without SPD chip

I'm talking about it.
Timings can (almost) always be set in the BIOS setup.
Systems based on DDR-RAM almost always do not boot without SPD. Exception to SIS, its will also boot with DD2 without or corrupted SPD.

FYI. Certain the reason for not booting without spd is due to the bios, Not the chipset or type of ram.

these are empirical observations

ElectroSoldier wrote on 2023-08-04, 01:38:

The only thing I can think of that would use 16Mb of PC100 is an industrial computer.

Like 128 and 256 DDR2 or DDr3.
Only example I know is exactly industrial machines that need a bare minimum.