CPS3 - How to convert 32Mb SIMMs into a 128Mb SIMM

[goguelnikov]

are you sure that you used N type and R type where it corresponds?

I think, but I’ll check. Each chip has its small dot in front of the triangle on the PCB.
Maybe some of the chips are damaged or fake...

 

[goguelnikov]

hello
finally, on of my upgraded SIMM is working, but not the other.
my setup is :

• slot 1 - 64MB
• slot 2 - 64MB (not required)
• slot 3 - 128MB working
• slot 4 - 128MB (32MB upgraded to be tested)
• slot 5 - 128MB working (only 32MB required)

When installing SFIII NG, it stops at 54%. I have an error in japanese telling "Can't write". Is there a way to identity which SIMM and chip on SIMM in slot 4 is not working ?
thanks

 

[goguelnikov]

So it finaly works!
i bought 3 32 Mb Simms on eBay and I manage to convert 2 of them into 128 Mb. I only have one 32 Mb Simm not working... I don’t know why...
Thank you for this thread!

 

[cruzlink2]

Now we are finished with the reverse pinout ICs. Next, we'll start soldering the normal pinout ones. One thing is important placing the flash ICs correctly. You'll notice that there are triangle marks on the PCB. These triangle marks indicate the #1 leg of the IC should be located there. The flash ICs have a tiny circle on them (they also do have a larger circle but that is something else) indicating the #1 pin.

I put circle on the photo to help explain what I mean...

With the same soldering technique I solder the normal pinout flash ICs one by one...

And the other side...

Top view... All in place, we are finished

Don't forget to clean the flux with IPA and/or Acetone and double and triple check the legs with magnifying glass one more time. Sometimes your iron tip may accidentally touch the neighbor IC leaving a solder bridge that you may have not noticed...

Anyway, after cleaning and examining twice, this is what we end up; One empty PCB one 128Mbit SIMM

And the ultimate question! Will it work?

Anyone knows the vaule of the small bypass caps?

 

[cruzlink2]

Thanks for this thread @yavuzg .

 

[tiff_lee]

Thanks for this thread @yavuzg .

Are those Fujitsu 90PTFR and 90PTFN chips? where did you source them? I've tried several suppliers and either get PTFN when it should be PTFR or I get slower speed (120) chips.

Edit: To clarify I can see the fujisu logo and looks like PFTR chips (pic is little blurry on the markings) Just be good to know of a reliable source that is actually sending the product they're selling.