VOGONS


First post, by Andry

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Hi,

I own two Diamond 3DFX Voodoo 1 cards. One of them lacks a component labeled L9 (no video output when switch to 3DFX mode).

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I moved it from the working card to the other and it works great too.

I'm not able to understand what kind of component is L9. I suppose it is an inductor, but my little tester detect it as 0,3 Ohm resistance.

Does someone have an idea about this component?

Thank you!

Andrea

Reply 2 of 7, by stef80

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I had this situation with Diamond V1. There is no schematics for it, but there is for V2 from Creative. Should be similar/same value.
Repairing Diamond Monster 3D (Voodoo 4MB) - help needed

Reply 3 of 7, by sdz

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It's just for filtering, for testing you can use a piece of wire and the card will work.
It looks like it's used for RAMDAC power filtering, use a ~600R@100MHz ferrite bead, 1206 package, >0.5A.

Reply 4 of 7, by Thermalwrong

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sdz wrote on 2023-11-28, 19:01:

It's just for filtering, for testing you can use a piece of wire and the card will work.
It looks like it's used for RAMDAC power filtering, use a ~600R@100MHz ferrite bead, 1206 package, >0.5A.

Thank you 😀 I've been following along as well since the 3Dfx Voodoo 1 that I fixed the RAMDAC on still has terrible wobbly video output in 3D mode. It's got random inductors fitted and perhaps they're not the right specification or power output.

How did you determine the value needed?

Reply 6 of 7, by Thermalwrong

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sdz wrote on 2023-11-29, 16:56:

I measured all the components on two Voodoo 2 cards, and the OG Voodoo has the same RAMDAC.

Voodoo 2 component map

Aha, I hadn't spotted that thread and seen that you have the tools and the knowledge to test these parts accurately - very cool!
I'm only using one of those atmega transistor tester boxes but it's not adequate for testing inductance at least with my current skill level. Thank you for sharing that parts information, we should be able to save many more 3Dfx cards with that info 😀

I was hoping perhaps it was in that schematic for the arcade voodoo1 but the values for the inductors aren't really stated in there from what I can tell.

Reply 7 of 7, by Andry

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sdz wrote on 2023-11-28, 19:01:

It's just for filtering, for testing you can use a piece of wire and the card will work.
It looks like it's used for RAMDAC power filtering, use a ~600R@100MHz ferrite bead, 1206 package, >0.5A.

Thank you very much, I'll get required components!