Did all that and all that it does is preventing the system to boot.

Power rails were Ok, measured all resistors on the card and they were OK, eventually I discovered that the flash had two data pins shorted together, and after fixing that:

Signs of life!

Good work. Respect.

Thanks!

There's still a bit of work to be done, but at the moment the card works in single VSA mode:

Image is a bit wonky, but that's due to all those missing caps. It's also very bright, but that's normal for a V5 AGP/PCI on VGA output when the slave VSA is missing.
The master VSA and memory appear to work fine.
Time to add all the missing caps, VSA and 2 RAM ICs.

You have another GPU to soldering?

I have a couple, but I'll probably replace it tomorrow.
I already replaced everything else.

I really couldn't wait until tomorrow, so I soldered the VSA.

Good news: both VSAs appear to be working fine
Bad news: VGA output is still too bright and extremely nosiy at some resolutions.

Very nice work. How do you clean the flux off? Which flux do you use ?

Thanks! I use Chipquik NC191.
For cleaning I soak the board in IPA for a bit, then brush it, and while it's still wet I wash it with hot water(tap) and a brush. After you properly dry it, it looks perfect (unlike the card in my pictures, I'll give it a proper clean after I get it working).

Sometimes I also ultrasonic clean them, but filling and emptying the big ultrasonic cleaner is a pain.

Added cooling and ran some benchmarks:

Single VSA:

Dual VSA:

During the benchmark the image is perfect, just way too bright. I'll check the VSA databook, there has to be some voltage/current reference for the integrated RAMDAC.

Edit:
Well, fixed the brightness issue.

R543 should be 31R not 5R.

What remains in noise in 2D and 3D mode.
1024x768, 1920x1080 and 1600x1024 are perfect, but anything else has horizontal jitter.
Could also be the crappy Dell LCD.

Edit 2:
It's the crappy Dell. It does the same thing with other VSA cards, and the image looks perfect at any resolution through a VGA to HDMI converter.

So it looks like the card works fine and can be considered fixed. I'll manufacure a PCI bracket for it and replace the 2.54mm pin header & VGA connector, as someone previously melted them, as well as the power connector, which looks quite nasty.
Also need to add some heatsinks/fans.

Amazing work. Well done.

Only a word for all: FANTASTIC!

Bravo!!!!!

Impressive work. What equipment did you use for reballing and soldering of the missing VSA chip?

Thanks guys!

@analog_programmer
Just a preheater and hot air station. Any will do.
For reballing, a reballing jig and a custom stencil (you can order one from JLC).