voodoo 2 - dead framebuffer? \ VOGONS

voodoo 2 - dead framebuffer?

Topic actions

First post, by stlouis1

Posted on 2023-11-22, 18:37

stlouis1 Offline

Rank Newbie

Rank: Newbie
Posts: 36
Joined: 2023-10-10, 13:43

Hey everyone,

I have a voodoo 2 here that I've had since 2002. Recently pulled it out for a k6-2 machine and it's one of a matching pair I have, but it has issues. Part of it seems to be my own fault due to careless storage as 8-9 pins on the bottom right corner of the framebuffer chip were bent and shorted together which I didn't notice before powering it on. I was able to straighten them with a razer blade but it still doesn't work. I found some info and ran mojo and below is what I get.

As a best guess at the moment, I'm figuring that FB chip is pooched given the FBI memory detected is 0 and FBI PowerOn Sense is 0 as well. the traces for those pins that were bent seem to lead to the FB memory so it makes sense to me that part of the FB is buggered

1DPMI: In DpmiHookFxMemmap, addr=e1000000, size=01000000
2DPMI: Loading fxmemmap.vxd
3DPMI: mapping e1000000 size 01000000
4VoodooMEssage:  pSST: 0x0 data0: 0x0 data1: 0xe1000001 fn: 0x1000000
5DPMI: VoodooMessage: NULL ptr
6Finally: 00000000
7Info for Voodoo board # 0:
8=====================================================
9Virtual Base Address:                       0xe1000000
10Physical Base Address:                      0xe1000008
11PCI Device Number:                          0xb
12Vendor ID:                                  0x121a
13Device ID:                                  0x2
14FBI Revision:                               2
15FBI Memory:                                 0 MB
16FBI PowerOn Sense:                          0x0
17TMU PowerOn Sense:                          0xdead
18FBI DAC Output Color Format:                24BPP
19Scan-Line Interleaved?                      No
20TMU Revision:                               57005
21Number TMUs:                                57005
22WARNING: Board 0:  Bogus number of TMUs (57005)!
23DpmiUnmapMemory

1sst1Init Routines: InitCode $Revision: 8 $
2sst1InitMapBoard(): BoardsInSystem = 1
3sst1InitMapBoard(): vAddr:0xe1000000 pAddr:0xe1000008 Dev:0xb Board:0
4sst1InitRegisters(): Setting TREX-to-FBI FIFO THRESHOLD to 0x8...
5sst1InitRegisters(): Setting PRELIM FT-CLK delay to 0x8...
6sst1InitDacDetect(): Entered...
7sst1InitDacDetectICS(): Entered...
8dacWr(0x7,0xb)
9dacRd(0x5,0x79)
10dacRd(0x5,0x2e)
11dacWr(0x7,0x1)
12dacRd(0x5,0x55)
13dacRd(0x5,0x49)
14dacWr(0x7,0x7)
15dacRd(0x5,0x71)
16dacRd(0x5,0x29)
17sst1InitDacDetectICS(): Exiting...
18sst1InitRegisters(): Storing TREX0INIT0=0x5441
19sst1InitRegisters(): Storing TREX0INIT1=0xf420
20sst1InitRegisters(): Storing TREX1INIT0=0x5441
21sst1InitRegisters(): Storing TREX1INIT1=0xf420
22sst1InitRegisters(): Storing TREX2INIT0=0x5441
23sst1InitRegisters(): Storing TREX2INIT1=0xf420
24sst1InitSetGrxClk(): Entered...
25dacWr(0x7,0xe)
26dacRd(0x5,0x0)
27dacWr(0x4,0xa)
28dacWr(0x5,0x7b)
29dacWr(0x5,0x6c)
30dacWr(0x4,0xe)
31dacWr(0x5,0x0)
32sst1InitSetGrxClk(): Resetting TMUs after clock change...
33sst1InitResetTmus(): Could not reset TMUs...

just wondering if anyone here might have a more experienced opinion before I get a replacement FB chip. I've had this card for 21 years and have no intention of letting it go that easily

Reply 1 of 3, by Thermalwrong

Posted on 2023-11-23, 03:14

Thermalwrong Offline

Rank Oldbie

Rank: Oldbie
Posts: 1902
Joined: 2018-03-18, 19:24
Location: England

Don't get a replacement FBI chip, it's working. To be clear, the FBI chip is managing PCI communication so if it detects in BIOS and mojo.exe detects it, the framebuffer chip itself is successfully performing most of its functions already.

The SST log file gives a clear indication of where the fault is:
1. The DAC is working
2. The TMUs are being initialised I think
3. It's failing out when it tries to reset the TMU, there can be a few causes of this, not really the FBI's fault

In this other thread someone had the same fault you've got, which was tracked down to a bad trace from the LS244 which provides the clock signals to the TMUs: Re: Voodoo 2 repair, missing legs on Chuck
Check out this video too: https://www.youtube.com/watch?v=tRFucW4uB5k
The big ASICs are much more resilient than the 25 year old PCBs they're attached to
See this thread for TMU pin information, we've confirmed the pinout for the TMU on the Voodoo 1 & Voodoo 2 are the same: 3Dfx Voodoo 1 - Low level hardware information and diagnostics thread

Maybe also check that the reset pin (pin 208) is soldered down solidly on both TMU chips, since it's right on the edge at pin 208 - I've found that pins on the edge are most likely to come loose over time.

Reply 2 of 3, by analog_programmer

Posted on 2023-11-23, 07:28

analog_programmer Offline

Rank Oldbie

Rank: Oldbie
Posts: 1370
Joined: 2023-06-22, 16:38
Location: eussr-idiocracy inhabitant

Try to resolder these bent pins to contact pads on the PCB.

P.S. You can always use the "Video" section of the forum for videocard's related topics instead of this more common section.

The word Idiot refers to a person with many ideas, especially stupid and harmful ideas.
This world goes south since everything's run by financiers and economists.
This isn't voice chat, yet some people overusing online communications talk and hear voices.

Reply 3 of 3, by stlouis1

Posted on 2023-11-25, 13:49

stlouis1 Offline

Rank Newbie

Rank: Newbie
Posts: 36
Joined: 2023-10-10, 13:43

I've looked over those posts, and doing some probing with my meter around the DAC, clock and reset pins. Mine is a rev 2.0 card (picture attached) so the layout is a bit different. Where those threads reference a 74AC244 IC, my card has a 74LXC04 IC according to this diagram I found here

download/file.php?id=91548&mode=view

That said, meting the clck pin 186 on both TMU's, I get continuity with 22 ohm resistance on one of the pins on the 74LXC04. So traces appear to be fine there

FBI pin 227 also connects to a pin on 74LXC04 just fine, again, 22 ohm resistance

I also checked pin 11 on the DAC to the 74LXC04 and again found continuity between one of the pins there, and the DAC.

The reset pin 208 on each TMU has continuity to pin 197 on the FBI as well

as far as the idea of broken traces between any of those, that doesn't seem to be the case, unless I missed something.... this isn't exactly my area of expertise by any means...

The pins in the lower right of the FBI have been resoldered though, not as pretty as it was, but the joints are good

Go to top of page Go to top of page

Back to General Old Hardware