Quantum3D 3dfx cards repair thread

  • PG_123 You're welcome!


    Card7(Quantum3D Obsidian2 X-24):



    Card installs fine, and is correctly detected by mojo.exe:



    Hower, it throws this error:


    This usually means that something is really wrong with it. I removed the daughtercard, and it throwed the same error.
    I then checked all FBI and TMU pins, checked all the traces, measured all resistors and verified that all RAM pins are actually soldered. Everything was fine.
    The FBI had some previous rework done, so I started with it. I removed the bottom 4 FBI RAM ICs, same error. Replaced the top 4 FBI RAM ICs, same error. Removed the FBI and then tried with a known good X-24 card in the system. It throwed the same error.
    At this point I soldered back the FBI and original RAM.

    The lesson here is that while the Q3D X-24 is almost identical to the Q3D 200SB, one is intended for the consumer market (X-24), while the other is intended for professional use.
    If the professional driver is installed, it will NOT work with the X-24. It will identify that the card is not an 200SB/200SBi and throw an error that normally indicates a faulty card (instead of just saying "use the right driver" or "incompatible card").
    While not a repair, I thought it is useful information. Use the appropriate driver or Fastvoodoo drivers (recommended only for testing, as using Fastvoodoo drivers on Q3D 200SB/200SBi/X-16/X-24 cards causes the TV out Chrontel encoder to get stupidly hot).

    Here's the card with some new solder joints, working fine with the consumer driver:





    Edited 2 times, last by sdz (January 14, 2025 at 8:00 PM).

  • Card8(Quantum3D Obsidian2 X-24)*:

    Mojo.exe found nothing wrong with the card, and the driver properly installs and detects the card.



    Running a 3D application results in a black screen, and the 3D application is frozen.

    I removed the daugther card, and without it installed it worked fine:

    Taking a closer look at the card, the FBI looks like crap. Somebody either replaced it or resoldered it at some point, but didn't clean it after.

    I plugged the card back in, and disabled the TMUs from autoexec.bat. The card worked fine like this:

    So it's either something wrong with the TMUs on the daugtercard, of the FBI<->TMU connection. Since the FBI already looked like that, I checked the pins, and found this one loose:

    Soldering it back on was really hard, the solder wouldn't stick to the pad or the pin. After doing this the card worked fine:


    While the card worked fine at this point, it's not good to leave it like this. The FBI area looks really bad, and the fact that solder doesn't stick implies corrosion:



    Next I removed the junked FBI, and this is how the PCB looked like:



    It was way worse than it looked. Cleaning those pads up so that they accepted new solder took about an hour, and I destroyed 1 JBC tip.

    After cleaning up it looks like this:

    And the card with a new FBI installed, working fine:



    All the corrosion was in the FBI area, on most of the pads. This happened because someone reworked it, and did not clean the flux. Some types of flux are corrosive, and can really mess the board if left there for a couple of years.
    There was also a broken cap on the daugthercard, that was replaced as well.

    Edited 2 times, last by sdz (January 15, 2025 at 7:40 AM).

  • Nice to ready this. It validates what i learned the Last days. I have the same issue. I soldered ~8 years ago some cards and now corrosion happens :(

    Also a Diamond Voodoo 1 is affected. If i find some time i will Check it and send Pictures. I didnt known about this issues With some Flux... Learned it the hard way in the Last days where i wondered why my old fixed cards have corrosion :(

    Thx for sharing all this stuff. Now i have to Clean and fix all fixed cards again. Hope i dont have to renove the chips.

    How did you Clean the Pads from corrosion? Was there maybe already some corrosion under the solder stop paint? It looks like i tsome cases. So you then remove the solder Stop and what to do to protect them from corrosion again (I have Kontakt 70 Super Spray Here but rarly use it)? And how to renove the Flux Safe (Kontakt LR?)? In my Case on the Voodoo 1 I think this Flux ist also unser the Chip where i cant Clean :( I only have a hot air solder Station. Idk If i could remove that Big Chips With it without damage other parts in the PCB?

    The bad boy I used and never thought about corrosion. Really bad decision:

    Not good :(

    Edited 6 times, last by PG_123 (September 23, 2024 at 2:23 AM).

  • Card9(Quantum3D 100SB)* :


    Card installs fine, both halves are detected in device manager:


    However, when trying to open the Q3D settins page:


    Running mojo under DOS just freezes:


    Without the two shade modules, the card works fine. With just a shade module installed on the left side of the card, mojo still freezes. With a shade module installed on the right, mojo doesn't freeze anymore, however, we can see a second issue. More on that later.



    So, the first and more major issue seems to be on the left side, when connecting the extra TMU.

    This is how the FBI and the two TMUs are connected:


    TMU0 solder joints are good, so are the passives in that area and the PCB traces. However, this pin of the J13 connector is loose:


    After soldering it back on, and with both shade modules installed, Q3D settings can be opened:


    But that's about it:


    Checking mojo again, with the two shade modules installed, we can see that the left part of the card seems ok, but the right part has an issue detecting the RAM of the extra TMU:


    Quickly inspecting the card on the microscope, the right Shade module connector (J17) is messed up:


    Judging by how it looks, it likely left the factory like that. A pre-bent connector was soldered, and a couple of the pins were never actually soldered to the board.

    After fixing that, the card fully works:


  • Card10(Quantum3D 100SB)* :


    Only half of it (the right half) is detected in device manager/by mojo:



    To at least detect the FBI, not much is needed. Just the PCI to PCI bridge working (which it seems to be, since the second FBI is detected), FBI power and the FBI properly connected to the PCI bus. RAMDAC, RAM etc is not needed to detect it as a PCI device.

    Checking the FBI0 area, a resistor connected to it is broken:


    This should be a 1k resistor, and it's open. After replacing it, and adding the shade modules:





    Why was that 1k resistor so important? It connects FBI pin 230 (PCI AD20 signal) to pin 224 (IDSEL pin). There is no way the device (FBI) would correctly work on the PCI bus with the IDSEL pin floating.

    Edited 2 times, last by sdz (January 14, 2025 at 8:09 PM).

  • Card11(Quantum3D Obsidian2 200SBi)*:



    Card seems to function properly, however, video output and video passthrough works only when the Medusa cable is tensioned in a certain way:



    Looking closer at the card, it had some mechanical impact in that area, the PCI bracket is bent, and so is the video connector:




    Inspecting the area under the microscope revealed that some of the pins had cracked solder joints:



    Resoldered all the pins, but that didn't actually solve the problem.
    It's possible that some traces or connector pins are broken, so I removed the video connector (would have done that anyway, since it wasn't possible to bend it back in position).




    The traces and connector were OK. However, when measuring the ferrite beads in this area, I got some inconsistent readings. If the board was slightly bent, the resistance would vary significantly.



    While they don't look cracked at all, here's what happened after gently touching them with the soldering iron:



    Replaced those ferrite beads, soldered back the video connector, and straightened the PCI bracket in a vice:





    Card is working properly now.