zuldan wrote on Today, 10:53:

I’ve managed to find the identical 4ns chips. 2 weeks away. I’m also having a custom stencil cut for the NV15 (an off the shelf […]
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Trashbytes wrote on Yesterday, 05:01:

I had a look myself, seems like Alibaba China might be one of the few places with these specific chips available in the 4ns version...assuming you want to take that gamble.

I’ve managed to find the identical 4ns chips. 2 weeks away. I’m also having a custom stencil cut for the NV15 (an off the shelf one doesn’t exist) in case I have to reball the existing chip. I’ve also ordered some NV15 GF2 Ti chips in case the original NV15 GF2 Ultra is buggered. They should be drop in replacements. I’m determined to get this card working 😂

Trashbytes wrote on Yesterday, 05:01:

If you can find a Datasheet for these chips and you have a Oscilloscope you could check the data lines on each IC, my guess is the dead ones will have issues on the data lines which could help you find the bad ones.

I think the data would be so random on those lines it would be difficult to see something “odd”. I’m going to remove 1 chip as see what Mats reports.

That's the idea, itll either not be there or garbled, you shouldn't have any issue seeing a normal data pattern from the bad ones.

Trashbytes wrote on 57 minutes ago:

That's the idea, itll either not be there or garbled, you shouldn't have any issue seeing a normal data pattern from the bad ones.

I could probe a few data lines but I got no idea how they work. Does a data line do read and write or only certain ones do writes. To probe them properly without shorting something I would need a AGP riser cable. The one I have isn’t great. Most AGP cards don’t work with it. If you know of any, let me know.

zuldan wrote on Today, 10:53:

I’ve managed to find the identical 4ns chips. 2 weeks away. I’m also having a custom stencil cut for the NV15 (an off the shelf […]
Show full quote

Trashbytes wrote on Yesterday, 05:01:

I had a look myself, seems like Alibaba China might be one of the few places with these specific chips available in the 4ns version...assuming you want to take that gamble.

I’ve managed to find the identical 4ns chips. 2 weeks away. I’m also having a custom stencil cut for the NV15 (an off the shelf one doesn’t exist) in case I have to reball the existing chip. I’ve also ordered some NV15 GF2 Ti chips in case the original NV15 GF2 Ultra is buggered. They should be drop in replacements. I’m determined to get this card working 😂

Trashbytes wrote on Yesterday, 05:01:

If you can find a Datasheet for these chips and you have a Oscilloscope you could check the data lines on each IC, my guess is the dead ones will have issues on the data lines which could help you find the bad ones.

I think the data would be so random on those lines it would be difficult to see something “odd”. I’m going to remove 1 chip as see what Mats reports.

This is not as unhelpful as it might sound. On my last 9500 pro repair i could identify the data lines not getting data. It's usually all or nothing. So launching the card in an OS with constant output and then probing the data lanes can already tell you a bit. You don't need to understand the data, but check if the pattern is similar and if there are some that look off.

Instead of removing a whole memory chip, go and remove a 4pack series termination resistor network. It should translate 1to1 with 4 bits failing.