Unbelievable. Very much appreciated!

ChrisK wrote on 2026-02-18, 13:13:

Unbelievable. Very much appreciated!

Very welcome. The X700 AGP is basically the X700SE PCIe but with the full chip enabled. They went for DDR1 due to cost.

tehsiggi wrote on 2026-02-18, 07:52:

Keep it up! Regarding the schematic, there you go!

I wonder if there is any issue with memory, as the pattern with the colors in your first picture is very repetitive.. you could try to find a version of MATS for that cart RAM chips layout on Quadro 980 XGL

Whoa, that was way fast! Thanks for the schematic! This is close enough to the NV28 on my card (NV28 seems to have a few extra capacitors at the outer top left/right edge and center bottom-middle) that with a reference image with color differentiated capacitors, I am able to determine the values of the capacitors that need help.

The schematic + external reference image confirmed my suspicion that my card's cap colors didn't make sense. Of course, my first attempt with the shoehorned 2000pF capacitors was the actual closest to actual spec.🤣 The 4.7uF 0805s that I put in are correct, but I got the 0.01uF capacitor on the data lines wrong by a factor of 5 (I put in a 2000pF), whoops.

On the point about memory, the artifacts could have been caused by trapped isopropyl under the chip(s) from when I was cleaning flux off after attempt #2 or a result of the capacitor values from that attempt. The benchmark screenshot from my previous post was made after attempt #3 and ran without any artifacts (I was watching the whole time), so I would hope that the memory is ok. In any case, I am going to hold off on trying MATS until I get the correct value caps back on. I will update when I have news to share! 👍

Attempt #4 using the schematic specs completed. All done with this one I think. Embarrassingly, it seems that my display setup (PC -> Extron VGA splitter -> monitor) was the main culprit behind the smearing/ghosting with this particular card. 🤦

Performance is fine, no artifacts on benchmarks, only one minor issue remains that isn't a deal breaker: There is coil whine or some other squealing in the 10-14kHz range from the card that starts as soon as I power on the PC but goes away and stays away the moment I put a load on the card, i.e. start a 3d mark run. This problem persists with a different fan plugged in and doesn't seem to happen at all if I disconnect the fan. I always thought that coil whine was positively correlated with component load, but I guess that's not always necessarily true. 🤷

Hot air station is still a few weeks out, so eventually I might try to get the mlccs to sit a little more flush using it, though I don't know or think it really matters all too much.

Whining of the regulator could be due to the compensation network of the switching regulator not matching the output stage with the new caps.

Glad the card works.

tehsiggi wrote on 2026-02-22, 21:18:

Whining of the regulator could be due to the compensation network of the switching regulator not matching the output stage with the new caps.

Glad the card works.

You nailed it again! I looked at the schematic for the specs of the big electrolytics. Indeed, the big tall cap in the previous post needed an ESR in the range of 170mOhm and the one directly above it needed a bit more resistance as well. I finally got to use caps that I salvaged to practice desoldering years ago for something. No more high pitch whining! And I can finally justify having random caps on hand. 😆