VOGONS


Newly made 4MB 30pin SIMMs

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Reply 40 of 53, by Tiido

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I made the board myself and all are hand assembled and tested too. It costs 6.25€ to send them to Chile, with tracking. It might be cheaper for you to get them from USA though.
30 to 72pin adaptor is not in the todo list at all, you can buy any sized 72pin SIMMs for very low cost compared to the 30pin ones.

RayeR wrote:

That was a 1st prototype, just a test if it will work. He wrote that if it works he make new better layout and he probably did. I didn't check later as I still have some spare SIMMs so I'm not personally interested. Anyway in this case the traces on such speed are not critical, traces between SIMM slots and chipsets are many times longer...

It may not matter in the end but I like the idea that my thing is in no way responsible for any additional deficiency, theoretical or not. These were made with aspirations of pushing out the absolute maximum out any board around (DRAM chips notwithstanding 🤣). Layout always follows best practices, with care to reduce inductances and impedances to the minimum possible in the design. I do have noticed that large motherboards with big distance between RAM, CPU and cache do not overclock or tolerate tight timings nearly as well as more compact things, this is the main reason 33MHz stuck around for so long. I never use 33MHz and always do 40MHz or beyond and everything must be able to handle it.

imi wrote:

also I like your logo 😀

🤣, thänk you ~

T-04YBSC, a new YMF71x based sound card & Official VOGONS thread about it
Newly made 4MB 60ns 30pin SIMMs ~
mida sa loed ? nagunii aru ei saa 😜

Reply 41 of 53, by Tiido

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These sticks are now 50MHz approved ! I have tested them at 50MHz on the same OPTi 895 chipset board and I had to add 1 wait state on reads, writes can stay at 0 vait states, all other settings at max with half speed refresh. Memtest86+ v4.10 passes to 1 test fine with zero errors in such config, with 0ws on reads it gets unstable and shows many errors. I'm pretty happy with this outcome ~

T-04YBSC, a new YMF71x based sound card & Official VOGONS thread about it
Newly made 4MB 60ns 30pin SIMMs ~
mida sa loed ? nagunii aru ei saa 😜

Reply 42 of 53, by maxtherabbit

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Tiido wrote:

These sticks are now 50MHz approved ! I have tested them at 50MHz on the same OPTi 895 chipset board and I had to add 1 wait state on reads, writes can stay at 0 vait states, all other settings at max with half speed refresh. Memtest86+ v4.10 passes to 1 test fine with zero errors in such config, with 0ws on reads it gets unstable and shows many errors. I'm pretty happy with this outcome ~

very nice

Reply 43 of 53, by OzzFan

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I wonder if these modules would help my 486 - though I'm not sure if it'll work without parity memory and my soldering skills are nil. Did you say that 60ns 4MB 30 pin modules can be found on eBay for those of us in the States?

A (mostly accurate) listing of my computer systems: http://www.shelteringoak.com/OzzNet/

Reply 44 of 53, by Tiido

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Last time I looked there certainly were a lot of them available on ebay from some USA sellers.

I will have more sticks available soon, I got the chips and PCBs and I will have to cook up a new batch and test them. No parity this time either.

Apparently my PCB design got cloned in Russia, a friend once showed a forum link where photos of my sticks were seen and then a little later in one post pretty much same design, with same fault in it too 🤣. Oh well 🤣

T-04YBSC, a new YMF71x based sound card & Official VOGONS thread about it
Newly made 4MB 60ns 30pin SIMMs ~
mida sa loed ? nagunii aru ei saa 😜

Reply 46 of 53, by Sphere478

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Um, hey. Can you make me some 72 pin simms

I would love to make some 128mb simms

In fact, I’d love to talk to you about the ram in my upcoming build. You obviously seem more knowledgeable on the subject than I am

🖥Craziest socket 7 build on a 430tx chipset
🖥Dual socket 7 build

Reply 47 of 53, by Tiido

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There are some 64/128MB 72pin ones going to be made but some other stuff will come first.

Here's the cloning : https://www.phantom.sannata.org/viewtopic.php … =34350&start=66
I don't know if there's any sale plans.

T-04YBSC, a new YMF71x based sound card & Official VOGONS thread about it
Newly made 4MB 60ns 30pin SIMMs ~
mida sa loed ? nagunii aru ei saa 😜

Reply 48 of 53, by Sphere478

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Tiido wrote on 2021-02-02, 05:34:

There are some 64/128MB 72pin ones going to be made but some other stuff will come first.

Here's the cloning : https://www.phantom.sannata.org/viewtopic.php … =34350&start=66
I don't know if there's any sale plans.

I actually just bought some 128s 🙁

this project is super cool though :p

🖥Craziest socket 7 build on a 430tx chipset
🖥Dual socket 7 build

Reply 49 of 53, by RayeR

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It seems now opensourced 😀
https://github.com/UpLateGeek/Let-s-Make-Some-Memories

Gigabyte GA-P67-DS3-B3, Core i7-2600K @4,5GHz, 4GB DDR3, 128GB SSD, GTX670(GF7900GT), SB Audigy + YMF724F + DreamBlaster combo

Reply 50 of 53, by Tiido

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These are from here : Let's make some memories (SIMMs)

T-04YBSC, a new YMF71x based sound card & Official VOGONS thread about it
Newly made 4MB 60ns 30pin SIMMs ~
mida sa loed ? nagunii aru ei saa 😜

Reply 51 of 53, by rmay635703

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GigAHerZ wrote on 2019-10-14, 12:51:

30pin SIMMs theoretically support higher amounts than 4MB. Why was 4MB chosen for the size? Are 8+MB modules less supported by motherboards,

Tiido wrote on 2019-10-14, 13:39:

30pin SIMMs come in 4 varieties, 256KB, 1MB, 4MB and 16MB, each adding one address line over previous,
16MB support is limited to only late boards
I would make some 16MB ones but finding the right DRAMs to use is not very easy/cost effective

Albeit rare double sided “32 pin Simms” existed

They fit the same 30pin slot electrically but came in
128k
512k
2mb
8mb
Sizes

I had an old 486 motherboard and manual that listed support for all the sim sizes listed above
I had an old laser printer with a 2mb 32pin simm in the flesh
I also had a 1mb 72pin simm

However most all motherboards did not support double sided Simms and were even very sensitive to 3 chip Simms making the bigger sizes moot.

The bigger 30pin Simms that do exist
we’re usually motherboard specific
and not necessarily supported by newer machines
certain Apple Mac and IBM systems had bigger density Simms but these are the exception and usually not compatible with off the shelf motherboards.
They were also very rare

The strangest Simms were 64kb and from a late 8086 system

Too bad things weren’t more standardized in the early days, would be interesting

Reply 52 of 53, by Tiido

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The 32 pin ones add a new RAS+CAS pair for the other side so that there is no need for extra logic on the module itself to create them. I have seen some sticks that do though, Apple orientated ones IIRC.

T-04YBSC, a new YMF71x based sound card & Official VOGONS thread about it
Newly made 4MB 60ns 30pin SIMMs ~
mida sa loed ? nagunii aru ei saa 😜

Reply 53 of 53, by wiretap

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Awesome project. Don't know how I missed it. I just ordered parts/boards for a set of 10. Came out of $3 per SIMM, non-parity version.

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