Getting The 7th Guest/11th Hour working on real hardware was a giant pain back in the day. I recall a friend with a ET4000 having similar problems.

I remember trying to run The 11th Hour (either the demo or the full game, I don't remember) on an ET4000 ISA card, and it would refuse to run. I believe it required VBE 2.0 with linear framebuffer support, which only PCI and VLB graphics cards could provide. (Not sure about EISA graphics cards, but those are quite rare. Anybody?) I believe this requirement was due to the high-res full motion video scenes in the game, which were quite impressive for the time. The speed required to draw enough frames per second at 640x480 resolutions at 15-bit or 16-bit color depth just couldn't be reached through bank switching. The video in this game used scanlines, but it was probably still too much for ISA hardware to pull off.

I had just upgraded to a Pentium 100 by replacing the motherboard in my PC, but was still using my ISA graphics card and postponing the video card upgrade and saving up some more money for it.

Once I had upgraded the video card to a Diamond card with an S3 TRIO 64V+ chip, the game finally ran on my system.

If I remember correctly, the Diamond card's BIOS didn't support VBE 2.0 out of the box, but the SciTech universal VBE driver that was bundled with the 11th Hour detected the card and handled the VBE 2.0 support.

I later learned that universal VBE drivers shipped with some games tended to be outdated and cause problems with some newer graphics cards. The trick in such cases was to manually load a more up-to-date version of the universal VBE 2.0 driver before running the game. My guess is that upgrading the video BIOS to a version with integrated VBE 2.0 would also work, if such an upgrade were available for your particular graphics card. But this still wouldn't work for card that didn't support linear frame buffers, which was a hardware feature.

TL;DR: you need a PCI or VLB card with linear frame buffer support to run The 11th Hour, and if the card doesn't have VBE 2.0 (or higher) integrated in its video BIOS and the universal VBE driver bundled with the game doesn't recognize the card either, you'll also need to load a VBE 2.0 or 3.0 driver that supports the card, before you run the game.

Just try the last version of SciTech Display Doctor or UNIVESA that was ever released. If that doesn't support your card, I'm not sure what will.

Any ideas for other games to test the 16-bit color modes on the ET4000AX?

superfury wrote on 2021-02-10, 15:01:

Any ideas for other games to test the 16-bit color modes on the ET4000AX?

That's a good question. I know that Simcity 2000 ran on my ET4000 ISA card and used 640x480 resolution, but I'm not sure at what color depth. It may have been just 256 colors.

It may have simply been the case that cards that didn't have linear frame buffer support simply weren't fast enough to run fast-paced games in high-color modes. Before the 3dfx Voodoo cards came out, I distinctly remember that I could never get any game to play at 640x480 with a smooth frame rate. Computers were simply not fast enough to do that without 3D hardware accelerators.

So your best bet would be some kind of strategy game, or perhaps a later graphics adventure.

Maybe you could try some Windows 3.x games? Specifically games that supported the WinG API? I'm not sure if any of them used 16-bit colors, or if WinG would also work on video cards without a linear framebuffer. But it might be interesting to find out. Good luck! 🙂