Tip: Using Sci-Tech Display Doctor AND your Video Board Driver

By Daniel Caetano

The first thing you should be asking yourself: "Why do such strange thing?" But there is no secret on this. One day I was trying to run SNES9x for OS/2, and I discovered that the program needs the SDD Helper to be installed so it can use MGL routines to control full-screen video mode.

At first I did not like the idea, because I thought the SDD drivers must be installed to use the SDDHELP.SYS, and once I use a Matrox Millennium II, which has GREAT drivers for OS/2, this was a very bad idea... I had two reasons to thought that way:

The Matrox drivers are a lot faster than Sci-Tech Display Doctor ones (benchmarked!) Sci-Tech drivers (GRADD itself, not fault of Sci-Tech) do not let me select interlaced video modes for Presentations Manager, and once I like to use 1024x768 in my 14 inch interlaced SVGA monitor, this is a real problem for me.

But then I send an e-mail to SNES9x for OS/2 author, and he told me that just placing SDDHELP.SYS, without changing the video driver, would be sufficient to run SNES9x. And I successfully do this task. But the result was not the result I would like to get, because only fixed modes (640x480, 800x600, 1024x768...) were available in this way... and I had to play SNES games in a small portion of the screen.

I wanted to see SNES9x running FULL-SCREEN! So I remembered that the SDD had a utility to "add" new screen modes, and then I installed SciTech drivers, planning to go back to Matrox drivers after I had played a little. After run SNES9x - a great emulator... very fast! - I started to reinstall Matrox drivers... but I forgot to go back to VGA mode and installed Matrox drivers OVER SDD... and after the installation... I boot the system and noticed that the SDDHELP.SYS had not been removed from Config.Sys, and surprisingly PM Shell and WPS started using Matrox drivers and no problem was detected...

"Let's try running SNES9x now..." I thought... And what was my surprise when I saw that SNES9x was running using the weird video mode (256x239) that was introduced when only SDD was installed. And then I remembered to check if the SDD utilities continued working ... well... some work, some doesn't work, but the main utilities STILL WORKING!!!

GACTRL.EXE (for centring/refresh control), GAGAMMA.EXE (correcting Gamma Level), GAMODE.EXE (install new "weird" video modes and refresh rates), GAMON.EXE (set your monitor) continued to run. Of course their settings only apply to non-PM video modes (OS/2 Full-screen modes), but this is everything we want!

Besides, take care with GAOPTION.EXE and GAREPORT.EXE. All times I run then my computer simply crashed with a black screen... only RESET and POWER buttons continued to work.

So, here is the deal: get the SciTech OS/2 Drivers at SciTech site, back your system to VGA Mode, install SciTech Drivers and then install your card specific video driver OVER SciTech drivers, without uninstall the SciTech drivers... and then reboot. After the reboot, everything should be working perfectly well.

Why not only install SDDHELP.SYS in the config.sys and copy the utilities? hehehe... After my "discover" I tried to do that, but I got crash with all SciTech programs on this way. Why? Because when you install SciTech drivers it installs some other files in a place called NUCLEUS and make some settings needed for all programs from SciTech package. And these settings are deleted when you uninstall the SciTech Package.

Note: DO THIS AT YOUR OWN RISK! The fact it worked in my computer, using Matrox Millennium II PCI drivers will not guarantee that it'll work on your computer with your video driver. I DO NOT GUARANTEE ANYTHING. This is an unsupported procedure. SciTech, Matrox neither me are responsible for any damage to your hardware/software by using this technique.