Hi there 😀

What happens if you try to use the pass-through cable for the display?
Also, is the monitor actually saying "No Signal" or is it displaying black?
If your multimeter supports Hz / clock measurement you can jam the positive probe into the VSYNC / HSYNC pins to see what the frequency of those presently is - I would've thought you'd have a display if the hsync and vsync are there even if it's displaying all black.

If the mojo test all looks good then that means the digital side of the RAMDAC is functional but perhaps there's a problem with the 3384Q display switch chip or the analogue power / outputs of the RAMDAC - you can see how I fixed mine here: Re: What retro activity did you get up to today?

Hi,
Thank you very much for your help!

Sadly I don't have a pass-through cable at the moment but the switching part is working I think, because without running something in 3D there are 0Vs on the RGB pins. After starting a game I can measure changing voltage on the RGB pins.

The monitor says no signal, the led is blinking then sometimes the led is on for a while then blinking again.
I will receive my oscilloscope this week, and will check what's going on the hsync/vsync side.

I also suspect that the culprit is on the analog output line.
Actually the card is in really good shape, no broken traces or something like that.

I think it's time to order some replacement RAMDACs, just in case 😁

I assume from the 3dmark score You are running this on something period correct?
Does You monitor support higher than 60hz? You can force the refresh rates to 60hz in the control panel.
Voodoo 1 cards sometimes don't work on higher mhz systems.

Dos 3dfx version of Tomb Raider is a good test as it avoids any possible windows software and driver issues.

Hey!
Thank you for the hints!

I've already tested it in 3 different boards, 430VX(P1 133Mhz)/440BX/some SiS soscketA board, and now I retested it in a 430HX socket7 board(6x86 120Mhz).
Also tried with SET SST_SCREENREFRESH=60 and SET SST_SCREENREZ=640 in autoexec.bat

Same results, no signal.

News!

I found a 2.5m long VGA extender cable, and checked the pass-through.
No signal either.

The cable itself looks ok, tested as an extender. The display became a little bit dimmer but otherwise works ok.

Maybe the QS3L384? How does the VGA signal leave the Voodoo 1? 😀

mrwolf wrote on 2023-12-14, 11:34:

News! […]
Show full quote

News!

I found a 2.5m long VGA extender cable, and checked the pass-through.
No signal either.

The cable itself looks ok, tested as an extender. The display became a little bit dimmer but otherwise works ok.

Maybe the QS3L384? How does the VGA signal leave the Voodoo 1? 😀

Check out this post, your Diamond card should be essentially the same arrangement: Re: 3Dfx Voodoo 1 - Low level hardware information and diagnostics thread
I'm not really sure what my notation meant, does VGA1 connect to VGA2? What's VGA2? How does that differ from pass-through? ehh - have a look at the really well laid-out schematic that Anthony posted in the last post, page 8 of that covers the switcher in a meaningful way 😀