Dolphin have tested Hal, Supernova and Lunar with numerous video cards from the Windows 95 and Windows NT 4.0 Hardware Compatibility Lists and didn't encounter any problems with these video cards.

However, it is possible for our products to encounter problems with some video cards due to either bugs in their video drivers, or that when implementing the drivers, the manufacturer hasn't adhered 100% to the operating system's video driver standards.   As a good rule of thumb, our products will work successfully with any video card that is on the Windows 95 or Windows NT 4.0 Hardware Compatibility List, or that has a Microsoft-supplied driver for it.

This problem is a little more common under Windows 95 because it's become common practice among some video card vendors to patch, bypass, or optimize the Windows GDI functions that screen readers and screen magnifiers hook into. Typically this is done in an effort to boost benchmark scores for magazine reviews and to earn design award consideration from OEMs, but occasionally a vendor does it for other purposes. However, this practice is now held in disregard by Microsoft and they are now actively working on getting these vendors to stop releasing video drivers that patch.

However, if you are unlucky enough to experience problems under Windows 95, you can get around these problems by setting the "Hardware acceleration" slider to "None" (or nearly none) in the "Performance" property sheet of the "System Properties" dialog box in the Windows 95 Control Panel.

Decreasing the "Hardware acceleration" slider swaps out functions that were performed by the video card's hardware (or in bespoke functions within the video card's mini-driver) and replaces them with functions from the Windows 95 DIB engine. i.e. Uses more reliable Microsoft-certified code.

Windows 95 contains a universal display driver called the device independent bitmap (DIB) engine. The DIB engine provides 32-bit graphics code for fast, robust drawing on high-resolution and frame buffer-type video cards. Windows 95 display mini-drivers use the DIB engine for all in-memory graphics operations and on-screen operations that aren't passed to the card for hardware acceleration. This architecture makes it easy for hardware developers to write drivers for new video cards and also to add hardware acceleration features incrementally.

To check if your video card is on Microsoft's Hardware Compatibilty List select this link.

For a list of video cards tested with Dolphin products select this hyperlink.

List of downloadable Microsoft Windows NT 4.0 video drivers.

How to create a Windows NT 4.0 Emergency Repair Disk (ERD).

Known video card problems under Windows 95

Microsoft Plus!

Microsoft Plus! has a font smoothing (or anti-aliasing) feature available in high-color mode. This smoothes the edge of TrueType fonts by inserting light and dark pixels into the gaps that would normally be the background color. This is incompatible with Lunar because when the anti-aliased font is enlarged it will loose its smoothed appearance.

Windows 95's DCI acceleration system

Lunar disables the DCI acceleration system to make Video for Windows compatible with Lunar's magnification system. You must run Lunar before starting any application that uses video clips.

DirectX and WinG

Games that use the DirectX or WinG systems for bypassing the display driver will not be magnified by Lunar.

QuickRes

Lunar and Hal are compatible with the standard QuickRes desktop resolution changer provided in the Windows 95 Resource Kit. However, do not use the version of QuickRes supplied with the Windows 95 PowerToys software pack with Lunar running. This version is patches the Windows GDI as is incompatible with Lunar and you will subsequently crash your system. In general, Hal and Lunar is not compatible with any resolution changer that changes the color depth of the display while they are running.

Video card drivers that do not support the Windows 95 DIB Engine

Video card drivers that do not support the DIB Engine won't work with Lunar's image smoothing facility. If the screen becomes very difficult to read when Lunar is loaded, then you can disable the image smoothing feature by editing the LW95CFG.INI file. Locate the [GLOBAL] section and add the line colour_changer=0.

Virtual desktops

Some video card drivers support virtual desktops (where the desktop is bigger than the resolution of the display).  Hal and Lunar will not work properly with these video cards unless you set the display area to be the same size as the desktop area.

Mach 64

Lunar's Line View mode does not synchronize properly with the display on some older ATI Mach 64 based cards, (Taxan GTS WinBoost and WinTurbo), causing the scrolling text to move too quickly. This is caused by a hardware fault in some Mach 64 video chips. The problem has been corrected in newer Mach 64 cards.

Matrox Millenium/Mystique MGA

To use Lunar with these video cards you may have to turn off the color changer (see above). Also you must change some of the video drivers settings.  Go into the Advanced Settings dialog box in the Matrox control panel and turn off "PowerGDI acceleration" and "Device Bitmaps Caching".  Lunar will then work correctly with these video cards.  Click here for assistance.

Number 9 Motion 330/531

The Number 9 Motion video drivers supplied with this card are not fully compatible with Lunar. (You may see some screen corruption) You should use the Microsoft Diamond Stealth S3 drivers supplied with Windows 95 instead.

Known video card problems under Windows NT Workstation 4.0

Font Smoothing

If you are using Hal for Windows NT Workstation 4.0 in 16-bit (or higher)
color mode, then you should make sure that "Smooth edges of screen fonts" is
turned off in the Display properties dialog box. (The Display properties
dialog box can be found in the Windows Control Panel.)  If you don't do this
then some text may not be seen by Hal, and therefore not spoken.