Sorry for resuming this very interesting thread!

I've replaced the RAM on my CT4520 (existing one was shorted) but the board now refuses to be detected. I've checked and re-checked everything. No shorts and each pin is going to either the EMU, the main chip or it's N/C-VCC-GND.

The chips I am using are SIEMENS HYB5118165BSJ-60 and they seem to be pin to pin compatible with the one used by @thermalwrong in the first post (which should be NEC 4218165-60 if I see that right).

And yes, I did move the 0-ohm resistors accordingly. I am familiar with soldering etc, I have a microscope and used a proper hot air station to remove the chip from the memory modules and to move the SMD resistor - I then solder the chip manually to limit the thermal stress to that old board.

Any ideas? The only three scenarios I can think of are
1. I made a mistake somewhere
2. The chip broke while removing/installing (I did test the memory modules before starting and they were passing a long memory test)
3. The chip is somehow not compatible with the board

Any ideas appreciated! 😀

Thanks
Tony

It could be that the PnP EEPROM happened to get corrupt, which will lead to the whole card not getting detected anymore. This has happened to me in past and fix was to rewrite the PnP EEPROM chip with new data.

Thank you!

I checked the Russian video linked in page one and I don't see any difference with what I did.

Tomorrow I will remove the chip and test again. If the board works, then I will try another chip.

I do have a programmer, could you share a link or a thread where I can learn more about the reprogramming if I needed that? Are you talking about an eeprom located on the sound card itself?

Thanks
Tony

Is the memory mod possible on the Ct3600? (SB32 PnP). I have one with no memory on board, and it would be cool if memory could be added.

I'm not familiar with Sound Blaster cards to be honest but by googling I do see pads for what might be a memory module.

tony359 wrote on 2022-10-25, 22:29:

I do have a programmer, could you share a link or a thread where I can learn more about the reprogramming if I needed that? Are you talking about an eeprom located on the sound card itself?

Yes, there's a little 8pin µwire EEPROM (93C66 or such) on the card where PnP info is stored and sometimes it gets corrupt. I have dumped a number of these : Creative PnP EEPROM collection

Amazingly thanks! I’ll see if the card works by removing the memory chip. If not I’ll take a look at that!

Bancho wrote on 2022-10-25, 22:34:

Is the memory mod possible on the Ct3600? (SB32 PnP). I have one with no memory on board, and it would be cool if memory could be added.

Is there a reason you don't just insert a pair of SIMMs? The CT3600 uses a PCB that is able to take a 256k x 16 DRAM chip, but it is easier and possibly cheaper to just add two 1MB SIMMs into the slots on that card, and at the same time you get four times as much memory. The CT3600 is not designed to work with 1M x 16 chips that could provide 2MB onboard memory.

@Tiido I found my eeprom was wildly different than the one you posted so I re-flashed it but the card did not work with that. Once flashed back to my backup, it worked again (with the RAM removed, it did not work with the RAM in place either).

So I assume there are multiple versions for different boards? I used a generic ATMEL 93C66 chip on the programmer as I could not find a 93C66S as in my case but I hope the S stands for SOP8, the package.

I'll add the backup to the other thread for future reference.

I'm back to square one. The memory module I used worked - I soldered it back to the memory module and it's running Windows 98 now 😀

I can see some scenarios here
1. The chip was not compatible with my card (unlikely?)
2. This card is somehow not upgradable to the 42pin version, they left the same PCB but for whatever reason it doesn't work
3. I made a mistake with the soldering which I did not catch. But honestly I tested pin by pin from them to a chip on the board so I know they were definitely going somewhere and not bridged.
4. The memory "section" of the chips (EMU8000 and AWE chip) is faulty (the previous broken module damaged it). But I'm puzzled why the previous module the card was still able to be detected and to work ok.

I've run out of ideas! Any help appreciated! 😀

mkarcher wrote on 2022-10-26, 13:45:

Bancho wrote on 2022-10-25, 22:34:

Is the memory mod possible on the Ct3600? (SB32 PnP). I have one with no memory on board, and it would be cool if memory could be added.

Is there a reason you don't just insert a pair of SIMMs? The CT3600 uses a PCB that is able to take a 256k x 16 DRAM chip, but it is easier and possibly cheaper to just add two 1MB SIMMs into the slots on that card, and at the same time you get four times as much memory. The CT3600 is not designed to work with 1M x 16 chips that could provide 2MB onboard memory.

The plastic on the simm slots is broken (I bought it very cheap because of that issue). Why is the CT3600 not designed to work with 2mb of ram? Is there a technical reason behind it?

Bancho wrote on 2022-10-26, 18:43:

The plastic on the simm slots is broken (I bought it very cheap because of that issue). Why is the CT3600 not designed to work with 2mb of ram? Is there a technical reason behind it?

It can work perfectly with 512KB of RAM, 2MB of RAM, 8MB of RAM or 32MB of RAM (28 of them usable). But 2MB chips have 42 pins whereas 512KB chips have just 40 pins. The AWE64 cards are designed in a way that they can take both kinds of chips. You use 0-ohm resistors to choose between the two pinout variants. The CT3600 is designed for 40-pin chips only. You would need to bodge the connections at one end of the chip to achieve a similar effect on the CT3600.

An interesting follow up (for me at least): I tried the memory swap, replaced the 0 Ohm jumpers, but not succeeded in installing the new chip (almost melted a hole in the pcb, removed the chip instead and cleaned the pads for no shorts), so it has no memory chip on my AWE64 Value until I have enough hot air gun practice. The card still works more or less: initializes fine, diagnose.exe succeeds (tries to detect memory, finds none, but gives no error just skips), 8 bit, 16 bit, awe synthetized tests sound fine, but the normal synthetized test (3rd option) has missing voices, only the lower half of the music plays. I don't think the missing memory causes this, it must have been my hot air.
So: if you do not wreck the card totally, it can be used for something, even with no memory chip...