Many third-party display drivers utilize virtual-device displays (VDD) and grabbers included in Windows 3.0. Combinations of Windows 3.0 VDDs and grabbers with their counterpart components included in Windows 3.1 may not be compatible. For example, a grabber designed to work with the standard VGA VDD included in Windows 3.0 (*VDDVGA) may not be compatible with the standard VGA VDD included in Windows 3.1.
In all cases for display drivers, whether it's Windows 3.0 or 3.1, you must create and distribute a Setup disk that contains VDDs and grabber files. Don't depend on the Windows retail product Setup disks for the distribution of these files.
Properly built third-party display driver OEM Setup disks will already include appropriate VDD and grabber files, and no changes should be required. Unfortunately, some vendors do not ship VDD and grabber files that are already available on the Windows 3.0 Setup disks.
If your driver installation disk provides a proprietary VDD, but relies on standard Windows 3.0 disks for a grabber, you should rebuild your installation disks to ensure compatibility with Windows 3.1.
Similarly, if your driver installation disk provides a proprietary grabber, but relies on standard Windows 3.0 disks for a VDD, you should rebuild your installation disks to ensure compatibility with Windows 3.1.
The driver installation disks must include all necessary files. You can determine the necessary files from the table below. In general, if your driver uses the specified Windows 3.0 file, your Setup disks should include the corresponding Windows 3.1 file.
| Windows 3.0 file | Windows 3.1 file | Description |
| *VDDVGA | VDDVGA30.386 | Windows 3.0 VGA virtual-display device. |
| This file is equivalent to the original VGA VDD embedded in the Windows 3.0 WIN386.EXE file. It should be used only with compatible 386 enhanced-mode grabbers, such as VGA30.3GR. | ||
| VGA.GR3 | VGA30.3GR | Windows 3.0 VGA 386 enhanced-mode grabber. |
| This file is equivalent to the original Windows 3.0 VGA 386 enhanced-mode grabber. It should be used only with compatible VDDs, such as VDDVGA30.386. | ||
| VDD8514.386 | VDD8514A.386 | Windows 3.0 8514/a virtual-display device. |
| This file is built from the Windows 3.1 EGA VDD source files, and contains minor updates since the release of the original Windows 3.0 8514/a VDD. It should be used only with compatible 386 enhanced-mode grabbers, such as V7V6A.3GR. | ||
| 8514.GR3 | V7V6A.3GR | Windows 3.0 V7V6A 386 enhanced-mode grabber. |
| This file is equivalent to the original Windows 3.0 8514/a 386 enhanced-mode grabber. It should be used only with compatible VDDs, such as VDD8514A.386. |
The Windows 3.1 DDK disks include Windows 3.0 versions of VDDs and grabbers previously described in the DISPLAY\WIN30 directory.
VGACOLOR.2GR, the Windows 3.1 standard-mode VGA color grabber, is compatible with drivers that use the Windows 3.0 version, VGACOLOR.GR2.
V7VGA.3GR, the Windows 3.1 version of the Video Seven 386 enhanced-mode grabber, is compatible with drivers that use the Windows 3.0 version, V7VGA.GR3.