First post, by strobo
When I was in elementary school we had our first PC at home. It had a Pentium II 400 MHz and a Matrox video card (G400 I think), running Windows 98 SE.
Now I remember that I wanted to play one particular game and it gave me one of these helpful error messages along the lines of "ahh so sorry, you need a 3D accelerator to play this game, please refer to the manual". My father then got me a used 3Dfx Voodoo and of course none of us had any idea what we were doing. It's very likely that it never actually accelerated anything at all until it was sold once we got an Athlon XP machine.
What I have kept is this fascination with the concept of having a separate 3D card with the external loop cable (it's not actually a loop, is it?) or maybe we can call it a trauma because this experience always kept creeping up to me, telling me to buy a Voodoo card and finally figure out what I have missed.
But I didn't just want to spend a bunch of money to solve the problem, I felt like I have to earn it so I bought a broken one.
As far as I can tell the seller was honest about the damage and seemed genuinely interested in the card being brought back to life. According to him it was stored with other unused, but not broken parts where the damage happened. Before selling it he had tried to solder some wire to the chip where the legs are missing and at some point made a picture of the card showing up in the device manager.
I do have a soldering iron, a (borrowed) hot air soldering station, some no-clean SMD flux and mediocre soldering skills. I'm quite optimistic. My analysis so far:
* the damaged chip is called Chuck
* two legs are missing: pin 255 = DEVSEL# and pin 256 = GND
** DEVSEL# input resistance is rising -> infinity. Good.
** diode voltage measured with multimeter from GND to DEVSEL# is 0.444V. Some internal protection diode seems to be intact?! Same on address pins.
* some other legs are bent (63-64, 245-256) and some are also off their pads a little (245, 253-254)
* C166 is missing and look somebody has posted a component map, how cool is that? Thanks sdz!
This is something I wanted to share with you but I also wonder if you have some repair advice. Replacing the capacitor should be easy. If I'm careful I should be able to fix the bent legs without ripping them off. The two missing legs are obviously the hardest part.
How about taking a small grinder like a Dremel to expose more of the legs - any experience with that? Otherwise I'll try to solder to what I'm seeing - maybe half a milimeter of metal. Find two really thin pieces of wire, hold them in parallel, then use hot air to solder?