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| Summary: | VESA Compatibility on Toshiba Computers |
| Date: | September 29, 1995 |
| Product: | As Listed |
| Problem / Issue: | Compatibility |
| Solution: | Driver Installation |
| Additional Information: | None |
With the start of a new standard, VESA (Video Electronics Standards Association) certain software applications now require VESA drivers. The VESA drivers are mainly the responsibility of the video chip manufacturer.
There is a VESA driver presently on the Toshiba of Canada BBS (905-470-7122) called VESAX.EXE (a self-extracting ZIP file) which is supported on the T4400SXC, T4400C, T6400 plasma, and T6400 colour
in 640x480x256 mode. This driver will also support the T4400SX-LCD and T4400SX-PLASMA in 640x400x256 mode both internally and through an external monitor. There will be a border at the top and bottom of the screen in 640x400x256 graphics mode. The 640x400x256 VESA driver was tested on the T4400SX-LCD.
Also available from the BBS, a file called TVEX24.SYS, which is also in the Companion Utility Diskette. This VESA device driver is designed for T1950CT, T3400/CT, T4700CT, T4800CT, and T6600C that has 1MB of Video RAM. These machines have Western Digital (WD90C24) video chips.
For machines with 512k video RAM such as T4500/C, T4600/C, or T4400SXC, there is a universal VESA driver SVGAKIT.EXE (a self extracting ZIP file) available from Toshiba BBS.
With 512k video RAM, VESA maximum resolution is 1024x768x16 (external CRT only), and with 1mb video RAM the maximum is 1024x768x256 (external CRT only)
Tips with VESA drivers
1. The specific driver to load in VESAX distribution is VESA.COM
2. TVEX24 must be installed in CONFIG.SYS:
DEVICE=<DRIVE>:<PATH>\TVEX24.SYS
3. SVGAKIT has one executable file UNIVESA.EXE that can be loaded at any time either from the DOS prompt or be included in AUTOEXEC.BAT.
4. The driver will work under basic conditions ie: With
HIMEM.SYS/EMM386.SYS/SMARTDRIVE.EXE/MSMOUSE Any other TSR might interfere with the VESA driver and cause failures which might hang the computer. Display.sys will interfere with the VESA driver.
5. If the program says that it is VESA compatible, then it is
absolutely necessary to have VESA drivers for your machine (video card). It will not work without it.
6. VESA will not increase video performance in ANY application. 7. TVEX24.SYS and UNIVESA.EXE VESA drivers will not work with machines that have 256k video RAM (ie. T1910/CS, T1950/CS).
For a list of video chips in Toshiba notebooks, please refer to TSB0248.TXT from Toshiba BBS (905-470-7122) or via Toshiba AUTOFAX document number 9027 (1-714-583-3800).
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Toshiba America Information Systems Inc. (" TAIS ") shall not be liable for damages of any kind for use of this information, Which is subject to change without notice. Copyright 1994, 1995 TAIS.