nzoomed wrote on 2020-08-16, 10:05:

is it possible to install 2MB on an ISA WD90C30 card? I've got a few of these cards, either half or the whole bank of 8 full of […]
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is it possible to install 2MB on an ISA WD90C30 card?
I've got a few of these cards, either half or the whole bank of 8 full of 256K chips.

Is it possible to install 512K chips in these to get 2MB?

I believe the chip is capable of 16 bit color, going by the modes in the driver settings, but it comes up with an error on boot which I suspect is because the DAC is likely not 16 bit capable.

Could I install a 16 bit color DAC as an upgrade?

According to the datasheet here http://vgamuseum.info/index.php/f-naq/item/48 … ital-wd90c30-lr , 1MB is the max .

As for 16-bit color, if the chip actually supports it but the external RAMDAC used does not, it may be possible to change the RAMDAC, but it will likely require a VGA BIOS that supports that specific RAMDAC model, AFAIK . Someone with better knowledge on this point will hopefully either confirm this or correct me .

darry wrote on 2020-08-16, 13:31:

nzoomed wrote on 2020-08-16, 10:05:

is it possible to install 2MB on an ISA WD90C30 card? I've got a few of these cards, either half or the whole bank of 8 full of […]
Show full quote

is it possible to install 2MB on an ISA WD90C30 card?
I've got a few of these cards, either half or the whole bank of 8 full of 256K chips.

Is it possible to install 512K chips in these to get 2MB?

I believe the chip is capable of 16 bit color, going by the modes in the driver settings, but it comes up with an error on boot which I suspect is because the DAC is likely not 16 bit capable.

Could I install a 16 bit color DAC as an upgrade?

According to the datasheet here http://vgamuseum.info/index.php/f-naq/item/48 … ital-wd90c30-lr , 1MB is the max .

As for 16-bit color, if the chip actually supports it but the external RAMDAC used does not, it may be possible to change the RAMDAC, but it will likely require a VGA BIOS that supports that specific RAMDAC model, AFAIK . Someone with better knowledge on this point will hopefully either confirm this or correct me .

OK I was suspecting that may be the case.
I've seen some 2MB cards out there, but they were the wd90c31 and vesa bus.

Its probably worth upgrading a card if its got a decent chipset and the DAC is easy to get and a BIOS can be modded easily enough.

Speedsys says its 760kb which i think is wrong because all my 8 chips are 256K