do they work?

how many mb? 32?

Can you take photos at right angle both sides so all text is readable? Afaik no one made "topless" type COB DIMMs. There were at least two companies making DIMMs using defective ram chips. Celetronix was co ran by Chuck Peddle (6502 cpu designer) https://archive.computerhistory.org/resources … 9-05-01-acc.pdf
patents SIMM https://patents.google.com/patent/WO1998007192A1
SDRAM DIMM https://patents.google.com/patent/WO2003073805A2
DDR https://patents.google.com/patent/US20030161198A1
Chuck also had patent for COB DIMMs https://patents.google.com/patent/US20030159278A1 and using PCB as cover https://patents.google.com/patent/USD520015S1 but I never saw one.

The other was Spectek (Microns internal component-recovery group). Spectek did proper packaging and end consumer couldnt tell they were buying remanufactured product.

>Peddle: I had a patent on how to use partial DRAM. And we turned that patent into a very large business making DRAM in Sri Lanka, in India, using reject die from Micron.

>Peddle: We buy the good ones in the front, probably about half price because they sell them about half
price. Although we buy them less than half price because a lot of them don't make the 50% numbers that
other people are looking for. And then the ones in the back, we basically almost get free because we can
use them up.

That business died when Micron stopped selling partials(reject dies) to anyone but their subsidiary SpecTech.
"SpecTek began at Micron in 1988 as a component-recovery group. In the two decades since its inception, the company has grown from an internal group to a manufacturing division; that experience has produced a product portfolio and reputation that makes SpecTek a leader in application-specific memory solutions.". Every time you buy Crucial you might be buying inferior SpecTek factory remanufactured/patched from defects product.

> We lost 4,500 jobs in a weekend when they stop selling partials.

Nowadays most Chinese no name/weird name (Kllisre, ZIFEI, TANBASSH, Rasalas) ram is made from defective partials. 99% of all SSD/flash drive/memory card market is also defective parts with clever firmware monkey patching around damage, with pristine chips going into server products.

photo of right side

no markings on the bottom?
Packaging sure fits patent description, maybe you scored trial run/samples of Celetronix DIMMs.

But do they work though?

rasz_pl wrote on 2022-12-19, 05:26:

no markings on the bottom?
Packaging sure fits patent description, maybe you scored trial run/samples of Celetronix DIMMs.

These look like 72p SIMMs though (I counted the pins, just to be sure). Did they trial DIMMs using a SIMM package?
These memory modules look familiar though, I may have seen them before. Following this thread.

oh wow you are right, they only look like DIMMs

rasz_pl wrote on 2022-12-26, 13:11:

oh wow you are right, they only look like DIMMs

You were fooled! 😜 But can happen to the best of us 😜

Anyway, at best at first glance they could look kinda like DDR (SDR has 2 notches and these modules don't), but then the central notch would still look different (the central notch on 72p SIMMs is shallower).

I always count the pins on older modules like these as there were so many different 'standards' around and it's easy to mix them up by assuming it is what it at first glance seems like.

Interesting modules at any rate.

Sphere478 wrote on 2022-12-16, 05:28:

do they work?

how many mb? 32?

If I absolutely had to gamble, I'd probably wager 4MB 😜

Tetrium wrote on 2022-12-26, 14:32:

Sphere478 wrote on 2022-12-16, 05:28:

do they work?

how many mb? 32?

If I absolutely had to gamble, I'd probably wager 4MB 😜

funny how a quick google for Ddm132s5-7, which leads to https://www.afrenterprises.com/manufacturer/v … nology/page-31/
lists it as 'Vlsi Ddm132s5-7 6195 4Mb 72-Pin 70Ns Memory'

Crazy

weedeewee wrote on 2022-12-26, 15:13:

Tetrium wrote on 2022-12-26, 14:32:

Sphere478 wrote on 2022-12-16, 05:28:

do they work?

how many mb? 32?

If I absolutely had to gamble, I'd probably wager 4MB 😜

funny how a quick google for Ddm132s5-7, which leads to https://www.afrenterprises.com/manufacturer/v … nology/page-31/
lists it as 'Vlsi Ddm132s5-7 6195 4Mb 72-Pin 70Ns Memory'

Doh, I didn't even try to do a google search. I assumed nothing could be found or why else create a new thread asking questions about it?
But the reason I assumed it was probably 4MB is because I have seen such modules before and they were either the same size, or were 30p which to me indicates these modules had to be very low memory size. Another giveaway is the -7, as only the oldest 72p modules (which are almost always also the lowest memory sizes) would be slower than -6.
I wasn't absolutely sure these modules are 4MB, they could have been 2MB for all I knew.

I'm fairly sure I've seen such modules before, though I'm unsure these were 72p. If I have similar modules, they are probably 30p.

I mean these particular modules are probably not very useful, but still interesting imo.

they are EDO 72p simms of course.
@Tetrium
About this thread: check my question in the 1st post... I was curious about inner construction of them.

PhatCJ recently posted these on discord

Sphere478 wrote on 2023-01-08, 08:39:

PhatCJ recently posted these on discord

Thanks for adding these here 🙂

Oh my, very large die.

Cheers,

So those arent partials. Someone was saving on packaging costs like 30pin TOPLESS simms.

btw I found another company making simms from partially defective chips in early nineties from UK - Memory Corporation plc aka Torridon plc http://www.adamsmith.com/case_memorycorporation.html One of the first SSD patents was filed by Torridon, later acquired by Micron.

I have found a lot of Doa memory complaints mentioning that brand so gotta wonder how reliable a “complex” package like that would be.

I recently found these on a https://theretroweb.com/motherboards/s/edom-wintech-mv008

The chips are shingled.

There's a sticker on the back saying they are guaranteed to by 60ns simms, but it looks like someone burned the end of the TMS44100 chips to keep anyone from verifying that.