I received the cache stick today after it was bouncing around in the limbo that is USPS these days.

I put it in my M919 V3.4b /w AMD 5x86 @133Mhz and it passed cachechk and topbench without issue. The listing states it was tested at 160Mhz by the seller. Phil's Quake benchmark saw the ~20% speed increase this processor gets when you switch L2 cache on and off.

The PCB does list 2019 on it so this does appear to be a new clone, not NOS. So it seems there is hope in the ability to max out these boards without breaking the bank.

Here's the author of that board 'jerryt74332' on this forum made them last year and put the design on EasyEDA for anyone to make up. Sourcing, installing and testing the cache chips is not a small feat so the guy you bought from did a lot of work too 😀
This is the thread that seems to have gone under the radar: PC CHIPS M919 Cache Module Clones

Thermalwrong wrote on 2020-12-12, 23:38:

Here's the author of that board 'jerryt74332' on this forum made them last year and put the design on EasyEDA for anyone to make up. Sourcing, installing and testing the cache chips is not a small feat so the guy you bought from did a lot of work too 😀
This is the thread that seems to have gone under the radar: PC CHIPS M919 Cache Module Clones

I saw that thread before, but it's been over a year since he's sold anything on eBay. I'm just happy to finally have gotten one without spending $150 like that crazy European is asking for in the one module you can find in a Google search.

I have to give major props to anyone creating PCB designs, and the people assembling full versions. I know how much of a pain it is to solder a board, even once you get a nice solder mask and hot air workflow going. Once you throw in the bill of materials, sale fees to eBay, CC, or other merchant portals, and finally self-employment taxes. You are normally making below minimum wage.

Oh good. I was actually trying to figure out where the PCB design, etc. was as I have an M919 board but no cache module.

Has any checked to see if the address lines for 512K and 1024K go to that cache slot? I suspect not.

I was also wondering if 10 or 12 ns cache chips have been sourced NOS.

cyclone3d wrote on 2020-12-13, 04:13:

Oh good. I was actually trying to figure out where the PCB design, etc. was as I have an M919 board but no cache module.

The seller got back to me and he's doing another small run over the holidays. In case you or anyone else wants to try for that before going through the process of building one yourself.

SScorpio wrote on 2020-12-13, 05:00:

cyclone3d wrote on 2020-12-13, 04:13:

Oh good. I was actually trying to figure out where the PCB design, etc. was as I have an M919 board but no cache module.

The seller got back to me and he's doing another small run over the holidays. In case you or anyone else wants to try for that before going through the process of building one yourself.

How much did you pay for the one you got?

cyclone3d wrote on 2020-12-13, 05:09:

How much did you pay for the one you got?

Search eBay for sold listings of m919 cache, but $45 + $4 s/h and state tax.

feipoa wrote on 2020-12-13, 04:47:

Has any checked to see if the address lines for 512K and 1024K go to that cache slot? I suspect not.

I was also wondering if 10 or 12 ns cache chips have been sourced NOS.

The date codes on the chips suggest years 2001 and 2000.

I have to dig up my M919 to check the address lines. Even if they don't go through the slot, there are many NC lines that can be repurposed.

Another auction listing was posted if anyone was waiting for it.

Any word on another batch, or even a kit and files?

I here's my coast module which apparently hasn't been documented yet.

It's a 01S3 stick but with Toshiba chips instead.

There's something else I also noticed which hasn't been pointed by anyone yet it seems :

This looks like jumpers, doesn't it ? Maybe that can be used to tell the motherboard which size is the COAST module ?

I have seen these "zero ohms" jumpers on several cache sticks. Unforunately they are undocumented in most cases. On some cache sticks they are used to change 3V / 5V Vcc for different SRAM and TAG-RAM chips. (Some demand both voltages, some don´t.)
I also have at least one stick where 256K <-> 512K can be selected when 2 or 4 SRAMs are present.

I documented the 0 ohm resistors in my handwritten notes I took pictures of and posted in the beginning of this thread.

I haven’t forgotten about this and actually after the success of the athlon golden fingers device I feel more comfortable ordering PCBs.

I have 200 or so pieces of the original 15ns cache chips. I have started work on tidying up Jerryt schematics and choosing the correct SMD parts for pick and place. Eventually I hope to get around to ordering and producing a batch of 20 of these.

I have ordered 100 chips to fix my cache module so if you share the schematic I might produce some as well 😀

Can someone post some benchmarks with and without cache on a 919 with an AMD 5x86 at stock 133 Mhz, or something similar?

I whipped up a design and layout for 1MB 3.3V M919 cache stick, will report back when I receive boards and parts and can test one. Hopefully just a couple weeks wait. Praying it works. Also have a 5x86-133 on the way so I can do some good comparisons of no L2 vs 256K vs 1M (predicated of course on the 1MB stick working)

You can expect 3 to 6% increase of performance going from 256 to 1024KB - it depends on the benchmark/game/app used - tested on Gigabyte GA-486AM/S board.

1MB stick works, how fun

pancakepuppy wrote on 2022-01-11, 20:27:

1MB stick works, how fun

Awesome work. Now I wonder if someone will shock the world and release the extremely delayed Pipeline Burst cache module. 😁