rasz_pl wrote on 2026-06-09, 18:32:

does the other one also map to 1GB?

Unfortunately I don't know how to check which address range is used by S3 Trio for VESA modes. Any ideas about the application which can check this?

The S3 VESA BIOS for the Trio64 does not support VESA 2.0 and thus has no LFB support. There is S3VBE20, but this is closed source software without any permission to create derivative works, and that software does not handle LFB for most VLB cards correctly. Possibly you can find some hint for educational use only on what's wrong with S3VBE20.

The S3 Trio64 driver for Windows does not attempt to use the LFB by default on VL cards, if I remember correctly. In any case, a sensible S3 Trio BIOS for a VL card will configure the LFB base address register of that card (on which a lot of bits are not acutally used by the hardware) to an address that is decoded to the LFB, so just reading that register might give an indication what address is used for the LFB. In case of the MK-765VL, as far as I know the address decoding is cloned from the STB card, so the LFB base address would be the same.