With a cold boot a central stripe (1/6 of the screen), blue background with letters/numbers in a pattern.
Could be a ram issue?
I'll post a pic when it'll happen again, as on reboot it doesn't show.

This is what it displays with a cold boot.

https://pdf1.alldatasheet.com/datasheet-pdf/v … I/TMS45160.html

This is the ram. 80ns.
Could it be a ram issue? Can i use another card's ram to try a swap?

Nexxen wrote on 2022-11-21, 15:13:

This is the ram. 80ns.
Could it be a ram issue?

I would be a fool to say "surely no" without careful testing, but getting the correct frequency from a Cirrus Logic chip doesn't require working RAM at all. Thus I conclude there has to be something different wrong with your card if your monitor refuses to sync to it.

Nexxen wrote on 2022-11-21, 15:13:

Can i use another card's ram to try a swap?

You can mix and match those 256K x 16 FPM RAM chips nearly as you like. There are two pinout variants: "Dual CAS" and "Dual WE", using a chip using the other pinout doesn't cause permanent damage. The chip you linked is "Dual CAS", recognizable by the two "CAS" pins UCAS and LCAS. Around the time of the Trio64/V+, EDO RAM started to appear on video cards, which might also be incompatible with cards designed for FPM.

mkarcher wrote on 2022-11-21, 15:36:

I would be a fool to say "surely no" without careful testing, but getting the correct frequency from a Cirrus Logic chip doesn't […]
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Nexxen wrote on 2022-11-21, 15:13:

This is the ram. 80ns.
Could it be a ram issue?

I would be a fool to say "surely no" without careful testing, but getting the correct frequency from a Cirrus Logic chip doesn't require working RAM at all. Thus I conclude there has to be something different wrong with your card if your monitor refuses to sync to it.

Nexxen wrote on 2022-11-21, 15:13:

Can i use another card's ram to try a swap?

You can mix and match those 256K x 16 FPM RAM chips nearly as you like. There are two pinout variants: "Dual CAS" and "Dual WE", using a chip using the other pinout doesn't cause permanent damage. The chip you linked is "Dual CAS", recognizable by the two "CAS" pins UCAS and LCAS. Around the time of the Trio64/V+, EDO RAM started to appear on video cards, which might also be incompatible with cards designed for FPM.

Thanks for the info.
On the card, what actually generated the signal? The GPU or another chip?

Nexxen wrote on 2022-11-21, 17:12:

On the card, what actually generated the signal? The GPU or another chip?

The GPU generates the pixel clock, the horizontal sync signal and the vertical sync signal. Every timing is derived from the 14.318 MHz crystal on the graphics board.

mkarcher wrote on 2022-11-21, 21:05:

Nexxen wrote on 2022-11-21, 17:12:

On the card, what actually generated the signal? The GPU or another chip?

The GPU generates the pixel clock, the horizontal sync signal and the vertical sync signal. Every timing is derived from the 14.318 MHz crystal on the graphics board.

I'll replace the crystal to see if had anything to do.

Afaik the frequency is programmed by the bios, without video bios running no output will be generated. Garbage on screen and bad frequencies make me think something wrong with ISA slot, or power supply to the card?

>Bios is working, I swapped it with another ISA card (CL-GD5420-750C-C) and it gives the same error, but on the ISA it displays everything fine. On the VLB still "out of range".

so the ISA card plugged in to ISA slot with VLB glued to its ass is also doing weird things? sure sounds like that ISA slot went bad

rasz_pl wrote on 2022-11-21, 22:50:

so the ISA card plugged in to ISA slot with VLB glued to its ass is also doing weird things? sure sounds like that ISA slot went bad

I don't understand this. No, I didn't "glue it to its ass". 😀

I took the bios chip from a GD5422, tried on VLB: same.
Tried VLB card Bios on ISA card: works as expected.
I tried the VLB card on all VLB slots, nothing changed.

I don't think it's the bios chip or data on it. Issue is somewhere else, but it's not easy like with all old things.

so again, does that:

>>Bios is working, I swapped it with another ISA card (CL-GD5420-750C-C) and it gives the same error, but on the ISA it displays everything fine. On the VLB still "out of range".

mean CL-GD5420-750C-C works fine in short only ISA slots, but fails when plugged into combined ISA/VLB slots?

rasz_pl wrote on 2022-11-22, 00:06:

so again, does that:

>>Bios is working, I swapped it with another ISA card (CL-GD5420-750C-C) and it gives the same error, but on the ISA it displays everything fine. On the VLB still "out of range".

mean CL-GD5420-750C-C works fine in short only ISA slots, but fails when plugged into combined ISA/VLB slots?

I was looking for a BIOS image to test if it was a BIOS issue.
I came across a site with Bioses and it stated that one of the images was a universal 542x model. Turned out it didn't work.

I have this ISA card with a 5422 chip, tried its bios chip to see if it worked on the VLB card.
Same problem.

To test the opposite, putting the VLB card's chip in the ISA card (the "swap"), the ISA card worked perfectly. No issues at all. I just ran Doom benchmark and it as fast as it should be.

My conclusion is that the card has a problem but not the bios, as it works.
The card worked until it didn't with that bios, can't rule it out 100% though, but I'm calling it close enough.

ah, so it was about swapping bioses, not trying working and tested ISA card in different ISA slots. never mind then.

Crystal was replaced but no change, still out of range.

This is what happens:
1) display bios info // out of range
2) blaks out in transition to mobo post info // goes black
3) bios post // out of range

Basically when it should output a signal the signal is not a valid input for the screen.

does ordinary ISA VGA card work in the same slot?

All ISA slots works with 16bit cards.
VLB slots work with VLB controllers 100%

To me it's a matter of signal not being processed correctly by the GD5428, 74F32PC (close to crystal) or MC74F245N (block of 4 close to sockets).
Can't guess anything else.

https://pdf1.alldatasheet.com/datasheet-pdf/v … LD/74F32PC.html

https://pdf1.alldatasheet.com/datasheet-pdf/v … /MC74F245N.html

You might need to try a different video BIOS, chances are another version has better video timings (they're all under software control).

Ok, it wad broken traces.
I feel like an idiot. 😀
But it was a straight cut, razor like, probably clashed against another sharp pin in the box it was stored. Took me 10 times and light at angle to spot it.

It was in fact connecting BUS to MC74F245N

Tiido wrote on 2022-11-23, 03:03:

You might need to try a different video BIOS, chances are another version has better video timings (they're all under software control).

I'll need a new rom, compatible, to make the upgrade.
Will do in the future.