VOGONS


Voodo0 repair attempt

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First post, by simonh27

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I am a complete novice with a soldering etc but I recently puchased a defective Diamond Monster 3D

Initially the memory was not detect and that turned out to be loose pins on the TMU so now it looks like everything is detected but when entering 3DFX mode I only get a black screen (tried with a passthrough and directly to the card)

Running mojo it all seems to be detected as should

Below is the log, anyone have any idea what the issue could be?

Thanks

sst1Init Routines: InitCode $Revision: 5 $
sst1InitMapBoard(): BoardsInSystem = 1
sst1InitMapBoard(): vAddr:0x10400000 pAddr:0xf6000008 Dev:0xe Board:0
sst1InitRegisters(): Setting TREX-to-FBI FIFO THRESHOLD to 0x8...
sst1InitRegisters(): Setting PRELIM FT-CLK delay to 0x8...
sst1InitDacDetect(): Entered...
sst1InitDacDetectICS(): Entered...
dacWr(0x7,0xb)
dacRd(0x5,0x79)
dacRd(0x5,0x2e)
dacWr(0x7,0x1)
dacRd(0x5,0x55)
dacRd(0x5,0x49)
dacWr(0x7,0x7)
dacRd(0x5,0x71)
dacRd(0x5,0x29)
sst1InitDacDetectICS(): Exiting...
sst1InitRegisters(): Storing TREX0INIT0=0x5441
sst1InitRegisters(): Storing TREX0INIT1=0xf420
sst1InitRegisters(): Storing TREX1INIT0=0x5441
sst1InitRegisters(): Storing TREX1INIT1=0xf420
sst1InitRegisters(): Storing TREX2INIT0=0x5441
sst1InitRegisters(): Storing TREX2INIT1=0xf420
sst1InitSetGrxClk(): Entered...
dacWr(0x7,0xe)
dacRd(0x5,0x0)
dacWr(0x4,0xa)
dacWr(0x5,0x7b)
dacWr(0x5,0x6c)
dacWr(0x4,0xe)
dacWr(0x5,0x0)
sst1InitRegisters(): Setting up FAST DRAM Configuration
sst1DeviceInfo: Board ID: Obsidian GE
sst1DeviceInfo: FbiConfig:0x2, TmuConfig:0x11
sst1DeviceInfo: FBI Revision:2, TMU Revison:1, Num TMUs:1
sst1DeviceInfo: FBI Memory:2, TMU[0] Memory:2
sst1DeviceInfo: Dac Type: ICS ICS5342
sst1DeviceInfo: SliDetect:0
sst1InitRegisters(): LFB Writes go through memory FIFO...
sst1InitRegisters(): TEXTURE Writes go through memory FIFO...
sst1InitRegisters(): exiting with status 1...
sst1InitShutdown(): Shutting down SST-1 #0...
sst1InitSetGrxClk(): Entered...
dacWr(0x7,0xe)
dacRd(0x5,0x0)
dacWr(0x4,0xa)
dacWr(0x5,0x41)
dacWr(0x5,0x62)
dacWr(0x4,0xe)
dacWr(0x5,0x0)
sst1InitShutdown(): Returning with status 1...

Reply 1 of 12, by CharlieFoxtrot

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AFAIK that log looks perfectly fine. There are no errors and chips basically do their thing. If there were loose pins already in TMU, card may have had some rough time and there may be other loose or missing components, such as SMD resistors or caps. Another option is burned or cracked SMD cap, which could all cause these kind of issues.

I would carefully go through the whole board, preferably under a microscope to make sure that everything looks as it should. And if you already have repaired loose pins, check also that they aren’t bridged and recheck every other chip and pins also with tweezers etc. so that they are surely attached properly.

It is a tedious job ahead, but my bet is that the card is repairable.

Reply 2 of 12, by simonh27

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CharlieFoxtrot wrote on 2025-07-07, 05:49:

AFAIK that log looks perfectly fine. There are no errors and chips basically do their thing. If there were loose pins already in TMU, card may have had some rough time and there may be other loose or missing components, such as SMD resistors or caps. Another option is burned or cracked SMD cap, which could all cause these kind of issues.

I would carefully go through the whole board, preferably under a microscope to make sure that everything looks as it should. And if you already have repaired loose pins, check also that they aren’t bridged and recheck every other chip and pins also with tweezers etc. so that they are surely attached properly.

It is a tedious job ahead, but my bet is that the card is repairable.

Thank you,

I ordered a microscope, hopefully I find something 😀

Reply 3 of 12, by Thermalwrong

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simonh27 wrote on 2025-07-06, 16:37:
I am a complete novice with a soldering etc but I recently puchased a defective Diamond Monster 3D […]
Show full quote

I am a complete novice with a soldering etc but I recently puchased a defective Diamond Monster 3D

Initially the memory was not detect and that turned out to be loose pins on the TMU so now it looks like everything is detected but when entering 3DFX mode I only get a black screen (tried with a passthrough and directly to the card)

Running mojo it all seems to be detected as should

Below is the log, anyone have any idea what the issue could be?

Thanks

Hmm I think CharlieFoxtrot is right in that your Mojo log output looks good. That means a whole bunch of things are working particularly on the digital side. But there are still a few things that could cause a blank screen because the analog vga part can have a few failure points.

Question 1: Does pass-through VGA work properly on the card?

Question 2: Have you checked all of the inductors / ferrite-beads around the RAMDAC on the front and back of the card?

Question 3: Do you have an oscilloscope? If so, could you check what frequencies you have on the HSYNC and VSYNC pins of the VGA connector in 3d mode? The reason I ask is that if pass-through works it narrows the fault down

------------------------------

Have a look at this thread I made on the Voodoo 1 for schematics and some repair logs: 3Dfx Voodoo 1 - Low level hardware information and diagnostics thread
The schematic that anthony included is the best one to look at because it's for the regular PCI card and includes all the video output stuff like the display switcher while the midway schematic does not.

My thinking is that the digital side of your card is all working, even the digital side of the RAMDAC, which is responding correctly.
But there's potentially a fault with either the RAMDAC's analog section from a broken ferrite-bead *or* there's a bad connection on the FBI since the FBI drives the hsync and vsync signals directly *or* maybe if there's damage at the front edge of the card then the R / G / B signals coming out of the RAMDAC could be damaged, that has happened to me: Re: What retro activity did you get up to today?

It may also be worth checking on a different PC, maybe the computer's too fast for the Voodoo 1 card?

Reply 4 of 12, by simonh27

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Thermalwrong wrote on 2025-07-10, 15:19:
Hmm I think CharlieFoxtrot is right in that your Mojo log output looks good. That means a whole bunch of things are working part […]
Show full quote
simonh27 wrote on 2025-07-06, 16:37:
I am a complete novice with a soldering etc but I recently puchased a defective Diamond Monster 3D […]
Show full quote

I am a complete novice with a soldering etc but I recently puchased a defective Diamond Monster 3D

Initially the memory was not detect and that turned out to be loose pins on the TMU so now it looks like everything is detected but when entering 3DFX mode I only get a black screen (tried with a passthrough and directly to the card)

Running mojo it all seems to be detected as should

Below is the log, anyone have any idea what the issue could be?

Thanks

Hmm I think CharlieFoxtrot is right in that your Mojo log output looks good. That means a whole bunch of things are working particularly on the digital side. But there are still a few things that could cause a blank screen because the analog vga part can have a few failure points.

Question 1: Does pass-through VGA work properly on the card?

Question 2: Have you checked all of the inductors / ferrite-beads around the RAMDAC on the front and back of the card?

Question 3: Do you have an oscilloscope? If so, could you check what frequencies you have on the HSYNC and VSYNC pins of the VGA connector in 3d mode? The reason I ask is that if pass-through works it narrows the fault down

------------------------------

Have a look at this thread I made on the Voodoo 1 for schematics and some repair logs: 3Dfx Voodoo 1 - Low level hardware information and diagnostics thread
The schematic that anthony included is the best one to look at because it's for the regular PCI card and includes all the video output stuff like the display switcher while the midway schematic does not.

My thinking is that the digital side of your card is all working, even the digital side of the RAMDAC, which is responding correctly.
But there's potentially a fault with either the RAMDAC's analog section from a broken ferrite-bead *or* there's a bad connection on the FBI since the FBI drives the hsync and vsync signals directly *or* maybe if there's damage at the front edge of the card then the R / G / B signals coming out of the RAMDAC could be damaged, that has happened to me: Re: What retro activity did you get up to today?

It may also be worth checking on a different PC, maybe the computer's too fast for the Voodoo 1 card?

I am using a P2 400mhz board

I do not have an oscilloscope and tbh I have no idea what ainductors / ferrite-beads are so I will need to research what they are and how to check them all I have is a multimeter atm

Thank you I will keep trying

Reply 5 of 12, by zuldan

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simonh27 wrote on 2025-07-06, 16:37:

I am a complete novice with a soldering etc but I recently puchased a defective Diamond Monster 3D

Initially the memory was not detect and that turned out to be loose pins on the TMU so now it looks like everything is detected but when entering 3DFX mode I only get a black screen (tried with a passthrough and directly to the card)

Curious to know how are you testing 3dfx mode. Are you running a game in DOS or Windows? What game are you trying to run?

Reply 6 of 12, by simonh27

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zuldan wrote on 2025-07-11, 13:26:

Curious to know how are you testing 3dfx mode. Are you running a game in DOS or Windows? What game are you trying to run?

Tombraider DOS edition as well as Turok in Windows 98

Reply 7 of 12, by Intel486dx33

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I would start with reflowing all the memory chips with solder paste and a heat gun.

Reply 8 of 12, by simonh27

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Intel486dx33 wrote on 2025-07-11, 14:28:

I would start with reflowing all the memory chips with solder paste and a heat gun.

That I can do as I have a rework station

Thanks

I will have time to have a crack at it again this weekend

Reply 9 of 12, by Thermalwrong

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simonh27 wrote on 2025-07-11, 13:08:
I am using a P2 400mhz board […]
Show full quote
Thermalwrong wrote on 2025-07-10, 15:19:
Hmm I think CharlieFoxtrot is right in that your Mojo log output looks good. That means a whole bunch of things are working part […]
Show full quote
simonh27 wrote on 2025-07-06, 16:37:
I am a complete novice with a soldering etc but I recently puchased a defective Diamond Monster 3D […]
Show full quote

I am a complete novice with a soldering etc but I recently puchased a defective Diamond Monster 3D

Initially the memory was not detect and that turned out to be loose pins on the TMU so now it looks like everything is detected but when entering 3DFX mode I only get a black screen (tried with a passthrough and directly to the card)

Running mojo it all seems to be detected as should

Below is the log, anyone have any idea what the issue could be?

Thanks

Hmm I think CharlieFoxtrot is right in that your Mojo log output looks good. That means a whole bunch of things are working particularly on the digital side. But there are still a few things that could cause a blank screen because the analog vga part can have a few failure points.

Question 1: Does pass-through VGA work properly on the card?

Question 2: Have you checked all of the inductors / ferrite-beads around the RAMDAC on the front and back of the card?

Question 3: Do you have an oscilloscope? If so, could you check what frequencies you have on the HSYNC and VSYNC pins of the VGA connector in 3d mode? The reason I ask is that if pass-through works it narrows the fault down

------------------------------

Have a look at this thread I made on the Voodoo 1 for schematics and some repair logs: 3Dfx Voodoo 1 - Low level hardware information and diagnostics thread
The schematic that anthony included is the best one to look at because it's for the regular PCI card and includes all the video output stuff like the display switcher while the midway schematic does not.

My thinking is that the digital side of your card is all working, even the digital side of the RAMDAC, which is responding correctly.
But there's potentially a fault with either the RAMDAC's analog section from a broken ferrite-bead *or* there's a bad connection on the FBI since the FBI drives the hsync and vsync signals directly *or* maybe if there's damage at the front edge of the card then the R / G / B signals coming out of the RAMDAC could be damaged, that has happened to me: Re: What retro activity did you get up to today?

It may also be worth checking on a different PC, maybe the computer's too fast for the Voodoo 1 card?

I am using a P2 400mhz board

I do not have an oscilloscope and tbh I have no idea what ainductors / ferrite-beads are so I will need to research what they are and how to check them all I have is a multimeter atm

Thank you I will keep trying

Ok, check these ferrite beads (L1 L2 etc) for continuity with the multimeter, they're little filters that reduce noise in the power supply to improve picture quality. Your card layout should be about the same as this one assuming it's one of the later revisions:

The attachment check-these-inductors.jpg is no longer available

My view is that the digital side of your card including the memory is probably okay since it's enumerating the ram for the frame buffer and texture memory properly, but reflowing them is pretty harmless and may resolve your issue. It did fix an issue I had with the diamond monster 3d in the above picture, which was showing black and blue stripes because of a loose leg on one chip of the framebuffer memory.

P2 400mhz should be fine in terms of speed 😀

Reply 10 of 12, by simonh27

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Thermalwrong wrote on 2025-07-11, 15:15:
Ok, check these ferrite beads (L1 L2 etc) for continuity with the multimeter, they're little filters that reduce noise in the po […]
Show full quote
simonh27 wrote on 2025-07-11, 13:08:
I am using a P2 400mhz board […]
Show full quote
Thermalwrong wrote on 2025-07-10, 15:19:
Hmm I think CharlieFoxtrot is right in that your Mojo log output looks good. That means a whole bunch of things are working part […]
Show full quote

Hmm I think CharlieFoxtrot is right in that your Mojo log output looks good. That means a whole bunch of things are working particularly on the digital side. But there are still a few things that could cause a blank screen because the analog vga part can have a few failure points.

Question 1: Does pass-through VGA work properly on the card?

Question 2: Have you checked all of the inductors / ferrite-beads around the RAMDAC on the front and back of the card?

Question 3: Do you have an oscilloscope? If so, could you check what frequencies you have on the HSYNC and VSYNC pins of the VGA connector in 3d mode? The reason I ask is that if pass-through works it narrows the fault down

------------------------------

Have a look at this thread I made on the Voodoo 1 for schematics and some repair logs: 3Dfx Voodoo 1 - Low level hardware information and diagnostics thread
The schematic that anthony included is the best one to look at because it's for the regular PCI card and includes all the video output stuff like the display switcher while the midway schematic does not.

My thinking is that the digital side of your card is all working, even the digital side of the RAMDAC, which is responding correctly.
But there's potentially a fault with either the RAMDAC's analog section from a broken ferrite-bead *or* there's a bad connection on the FBI since the FBI drives the hsync and vsync signals directly *or* maybe if there's damage at the front edge of the card then the R / G / B signals coming out of the RAMDAC could be damaged, that has happened to me: Re: What retro activity did you get up to today?

It may also be worth checking on a different PC, maybe the computer's too fast for the Voodoo 1 card?

I am using a P2 400mhz board

I do not have an oscilloscope and tbh I have no idea what ainductors / ferrite-beads are so I will need to research what they are and how to check them all I have is a multimeter atm

Thank you I will keep trying

Ok, check these ferrite beads (L1 L2 etc) for continuity with the multimeter, they're little filters that reduce noise in the power supply to improve picture quality. Your card layout should be about the same as this one assuming it's one of the later revisions:

The attachment check-these-inductors.jpg is no longer available

My view is that the digital side of your card including the memory is probably okay since it's enumerating the ram for the frame buffer and texture memory properly, but reflowing them is pretty harmless and may resolve your issue. It did fix an issue I had with the diamond monster 3d in the above picture, which was showing black and blue stripes because of a loose leg on one chip of the framebuffer memory.

P2 400mhz should be fine in terms of speed 😀

Am I looking for continuity to ground on both sides (i.e. bad cap?) or continuity through the actual ferrite bead

Reply 11 of 12, by Thermalwrong

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simonh27 wrote on 2025-07-11, 15:35:
Thermalwrong wrote on 2025-07-11, 15:15:
Ok, check these ferrite beads (L1 L2 etc) for continuity with the multimeter, they're little filters that reduce noise in the po […]
Show full quote
simonh27 wrote on 2025-07-11, 13:08:

I am using a P2 400mhz board

I do not have an oscilloscope and tbh I have no idea what ainductors / ferrite-beads are so I will need to research what they are and how to check them all I have is a multimeter atm

Thank you I will keep trying

Ok, check these ferrite beads (L1 L2 etc) for continuity with the multimeter, they're little filters that reduce noise in the power supply to improve picture quality. Your card layout should be about the same as this one assuming it's one of the later revisions:

The attachment check-these-inductors.jpg is no longer available

My view is that the digital side of your card including the memory is probably okay since it's enumerating the ram for the frame buffer and texture memory properly, but reflowing them is pretty harmless and may resolve your issue. It did fix an issue I had with the diamond monster 3d in the above picture, which was showing black and blue stripes because of a loose leg on one chip of the framebuffer memory.

P2 400mhz should be fine in terms of speed 😀

Am I looking for continuity to ground on both sides (i.e. bad cap?) or continuity through the actual ferrite bead

Just through it, one side to the other 😀 They're pretty prone to getting broken and the break is not really visible until it's removed with a soldering iron / hot air.

Reply 12 of 12, by simonh27

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Thermalwrong wrote on 2025-07-11, 15:49:
simonh27 wrote on 2025-07-11, 15:35:
Thermalwrong wrote on 2025-07-11, 15:15:
Ok, check these ferrite beads (L1 L2 etc) for continuity with the multimeter, they're little filters that reduce noise in the po […]
Show full quote

Ok, check these ferrite beads (L1 L2 etc) for continuity with the multimeter, they're little filters that reduce noise in the power supply to improve picture quality. Your card layout should be about the same as this one assuming it's one of the later revisions:

The attachment check-these-inductors.jpg is no longer available

My view is that the digital side of your card including the memory is probably okay since it's enumerating the ram for the frame buffer and texture memory properly, but reflowing them is pretty harmless and may resolve your issue. It did fix an issue I had with the diamond monster 3d in the above picture, which was showing black and blue stripes because of a loose leg on one chip of the framebuffer memory.

P2 400mhz should be fine in terms of speed 😀

Am I looking for continuity to ground on both sides (i.e. bad cap?) or continuity through the actual ferrite bead

Just through it, one side to the other 😀 They're pretty prone to getting broken and the break is not really visible until it's removed with a soldering iron / hot air.

Thank you 😀