Did you clean the PCI edge contacts on the card ? Use a new pink pencil eraser then use some Iso alcohol on paper towel. Also if the ROM is socketed press on it to make sure it is seated well.

Horun wrote on 2020-04-12, 22:56:

Did you clean the PCI edge contacts on the card ? Use a new pink pencil eraser then use some Iso alcohol on paper towel. Also if the ROM is socketed press on it to make sure it is seated well.

Yes I did that and repeated it today with a brand new eraser. I also checked the ROM. No luck unfortunately 🙁 card is still giving the same problems

Suggestion:
- Clean the Pci connectors with some Isopropyl Alcohol (IPA)
- Blow some air into the VGA connector (preferably with a can of compressed air)
- Remove the bracket and stick the card as far in as it would go, I suspect that isn't the original bracket.

aaronkatrini wrote on 2020-04-13, 22:42:

Suggestion: - Clean the Pci connectors with some Isopropyl Alcohol (IPA) - Blow some air into the VGA connector (preferably with […]
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Suggestion:
- Clean the Pci connectors with some Isopropyl Alcohol (IPA)
- Blow some air into the VGA connector (preferably with a can of compressed air)
- Remove the bracket and stick the card as far in as it would go, I suspect that isn't the original bracket.

Good point ! I thought about the bracket too but did some compares to others and it appears to be the right distance compared to the PCI slot edge connector though if it were not the original it could cause the front or back of the card to lift when tightened if bracket is off even a 1/16".

aaronkatrini wrote on 2020-04-13, 22:42:

Suggestion: - Clean the Pci connectors with some Isopropyl Alcohol (IPA) - Blow some air into the VGA connector (preferably with […]
Show full quote

Suggestion:
- Clean the Pci connectors with some Isopropyl Alcohol (IPA)
- Blow some air into the VGA connector (preferably with a can of compressed air)
- Remove the bracket and stick the card as far in as it would go, I suspect that isn't the original bracket.

Forgot to say, after cleaning the card, as suggested by Horun, I had the same idea so I removed the bracket and tried witout it. Still nothing changed 🙁 Althought the bracket seems to be of right lenght, even without it the card is visibly pushing against the back of the case (the thing that is pushing is vga connector). So you can imagine that with the bracket everything is even tighter. Never had such a tight card before. Surely something is wierd about this bracket/vga. I will try to completely remove the motherboard, so the card won’t be pushing against the case, and try it again.

I will also try again with compressed air and the connector itself. However, I used all my air and IPA yesterday and have to order some (cannot go to shop due to the quarantine in my country), so 1 or 2 days of waiting for me.

That's not a contact issue but more something like a bad RAM chip, which fails once heated up.

derSammler wrote on 2020-04-14, 07:47:

That's not a contact issue but more something like a bad RAM chip, which fails once heated up.

Good point, may be the case. Now if I will think about it... the card usually starts with a good picture (once connected after some time, so it can cool down), and starts to give problem after 2-3 minutes. If I recall correctly this does not happen when computer is just restarted, without giving card a chance to cool down.

Is it possible to check which RAM module can be the bad one? However, resoldering anything is probably not worth it. Remember Phil saying in one of his videos that MDRAMs are relatively expensive (have to check it).

You can check if one of the RAM chips is getting hotter than the others. That would be one indication of a bad chip. Another way is to use coolant spray on the chips to see if the error disappears when cooling a certain chip.

Also, I'm pretty sure the card will run with two instead of four RAM chips as well, with half of the video RAM of course. So if a chip is bad and you can identify it, downgrading the video RAM would be possible to make the card at least working correctly.

looks like a software problem to me. Maybe a driver issue. Before you mess with the ram. Try the card in another computer and slot or with a clean install.

If NOT then you may need to reflow the ram and GPU chip.
It's easy with a heat gun.
Just pour some No-Clean flux on the legs of the ram and gpu chip and then heat with a heat gun to the temp of solder melt which is about 250 degrees.
heat until all the flux is evaporated. let the flux do the work of repairing any bad or broken solder welds.
Should only take about 2 minutes of heating.
But don't try to bake the card in an oven. that is a bad way of doing it.
Use a heat gun.

Solder paste should work also.

OP has already said they tried it in other PCs.

I agree with the heat issue. potentially point a fan at the ram chips and see if it can delay the problem?

derSammler wrote on 2020-04-14, 08:14:

You can check if one of the RAM chips is getting hotter than the others. That would be one indication of a bad chip. Another way is to use coolant spray on the chips to see if the error disappears when cooling a certain chip.

Also, I'm pretty sure the card will run with two instead of four RAM chips as well, with half of the video RAM of course. So if a chip is bad and you can identify it, downgrading the video RAM would be possible to make the card at least working correctly.

Thanks for the useful tips! Now I have hope again 😀 Will try as you say today evening and share the results. This should give me some hints on the potential RAM problems. Even if I will have to desolder two RAMs, I think the same that the card should work with only half of the banks populated.

Intel486dx33 wrote on 2020-04-14, 08:42:

looks like a software problem to me. Maybe a driver issue. Before you mess with the ram. Try the card in another computer and s […]
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looks like a software problem to me. Maybe a driver issue. Before you mess with the ram. Try the card in another computer and slot or with a clean install.

If NOT then you may need to reflow the ram and GPU chip.
It's easy with a heat gun.
Just pour some No-Clean flux on the legs of the ram and gpu chip and then heat with a heat gun to the temp of solder melt which is about 250 degrees.
heat until all the flux is evaporated. let the flux do the work of repairing any bad or broken solder welds.
Should only take about 2 minutes of heating.
But don't try to bake the card in an oven. that is a bad way of doing it.
Use a heat gun.

Solder paste should work also.

Thank for the suggestions on the software side, however, I have already tried to run this card in a different setups (different slots, different computers, various monitors), still the same. I also tried fresh Windows installations (both Win95 and Win98SE).

As for the reflow, I will surely include you tips in my rescue/work plan! Will remember not to bake the card 😀 Will do the reflow before potential full desoldering of any RAM banks.

LewisRaz wrote on 2020-04-14, 09:41:

OP has already said they tried it in other PCs.

I agree with the heat issue. potentially point a fan at the ram chips and see if it can delay the problem?

Another great tip, thanks! As wrote before, today evening will do the test, before any reflowing/soldering jobs. Will share the results.

Yeah, I have never seen a bad ISA video card. But have seen plenty of bad PCI video cards.
Must have been the manufacturing solder process. I assume they used bad solder or baking process as these are surface mount chips onto the PCB.
But I have a box full of bad PCI video cards I have yet to try to fix by reflowing them.
But it does work. I have fixed some already. It you have NO video it is usually the GPU chip.
If you have video but garbled then it is usually the ram chips that need the reflow.

video
https://youtu.be/ZypXa9BDXHw

video
https://youtu.be/nyele3CIs-U

Intel486dx33 wrote on 2020-04-14, 11:40:

Yeah, I have never seen a bad ISA video card. But have seen plenty of bad PCI video cards. Must have been the manufacturing sold […]
Show full quote

Yeah, I have never seen a bad ISA video card. But have seen plenty of bad PCI video cards.
Must have been the manufacturing solder process. I assume they used bad solder or baking process as these are surface mount chips onto the PCB.
But I have a box full of bad PCI video cards I have yet to try to fix by reflowing them.
But it does work. I have fixed some already. It you have NO video it is usually the GPU chip.
If you have video but garbled then it is usually the ram chips that need the reflow.

video
https://youtu.be/ZypXa9BDXHw

video
https://youtu.be/nyele3CIs-U

Wow, thank you for the instructive videos! I really appreciate your help. Don't think that my soldering skills will allow me to do the drag-technique 😀 but hot-air gun soldering looks like something that I can easily handle. Just have to buy proper hot-air gun for this job. From what you are saying it looks like there is still a chance for my Tseng, and I have super interesting repair project in front of me!

Just did the suggested tests on my Tseng. The outcome is: none of the RAM chips seems to be hot or hotter than the others. Also, when cooling this part of the card with fan, the problems with the card still occur. Anyhow, I have ordered hot-air gun and couple other thing to do the repair. Once done I will share the results in this thread.

For the cooling test, you need coolant spray. There's no way to do that with a fan, as a fan can not make the chip cooler. A fan only helps heat dispersion so that the chip doesn't get hotter.

Instead of coolant spray, you may also use compressed air (from a can, not a compressor). If you hold the can upside down, the liquid gas is blown out, which has the same effect as coolant spray, but it will empty the can very fast.

The fact that the symptoms change when you wiggle the card makes me think there are some bad solder joints on one of the chips. Apply pressure with your thumb on each chip ("squeeze" the card, if you will), see if anything changes on-screen while you're doing that.