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XGA/2 for PC Q&A


Q: I have a non-Radius XGA, XGA-2, or XGA-2 compatible video card. Does Radius offer any drivers or support for this product?

A: If you have a third party XGA-2 video card manufactured by another company or if you have an IBM PS/2 with an XGA-2 built in video system, you should contact the manufacturer of your video card for updated drivers and support. Radius may not be familiar with non-Radius XGA, XGA-2 or XGA-2 compatible solutions and may not offer any type of adequate support for such products.

Q: After installing the Radius XGA-2 card into my computer and with no other cards installed, I do not get an image on my screen at startup or my computer does not start at all. What could I do to check the problem?

(Answer via faxed hard-copy only)

A: Check the configuration of the XGA-2 video card and your computer as follows:

For multiple video systems...

The Radius XGA-2 is a VGA compatible video card. If your computer offers a built in VGA compatible video system, make sure that you disable either that video system or the ROM on the Radius XGA-2 video card. Most systems which offer a built in video system also offer an option to disable or turn off the built in video and video ROM from dip switches or jumpers located on the computers motherboard. Some built in video systems can disable or turn off automatically if they detect that a VGA compatible video card such as the Radius XGA-2 is installed. Consult the documentation of your system to see how the built in video system can be disabled. If your built in video system cannot be disabled, you must disable the ROM on the Radius XGA-2 video card. To disable the ROM on the XGA-2 video card, you must turn switch 2 on bank SW2 to the off (down) position. This disables the VGA compatibility modes of the Radius XGA-2 video card. If you disable the VGA compatibility of the Radius XGA-2 video card, you must either have a second display connected to the Radius XGA-2 video card or you must utilize a "pass-through" cable between the built in video and the Radius XGA-2 video card. If utilizing a "pass-through" cable, your display should be connected to the Radius XGA-2 video card. When two video systems are used in this manner, keep in mind that only the Radius XGA-2 video card is used when XGA-2 type video drivers are selected from your application or from Windows. When the XGA-2 video drivers are being used, the built in video system will be turned off automatically.

Radius XGA-2 video card configuration...

Make sure that the Radius XGA-2 video card switches and jumpers are in their default settings. These settings will allow the Radius XGA-2 video card to properly boot on most computer systems without other cards installed and may be configured more appropriately upon adding other cards to the computer. The default settings for the Radius XGA-2 video card are as follows:

*Bank SW1 (bank of 4 switches)

1 and 2 turned off (down), 3 and 4 turned on (up).

These settings set the Radius XGA-2 card to ROM base address of C0000h.

*Bank SW2 (bank of 8 switches)

2 and 6 turned off (down), all others (1,3,4,5,7,8) turned on (up).

These settings set the Radius XGA-2 card to use DMA channel 7, XGA instance 6, and to use 8 or 16 bit memory and I/O cycles.

*Jumper JP1 (bank of 6 pins) (holding board upright with video port on right hand side).

Place this jumper on the 2 pins furthest to the left.

This sets the Radius XGA-2 board to use no wait states.

*Jumper JP2 (bank of 2 pins).

Place this jumper on both pins.

This jumper is reserved and should not be removed from the board.

*Jumper JP5 (bank of 10 pins) (holding board upright with video port on right hand side).

Place this jumper on the 2 pins in the center of the 5 rows.

This sets the Radius XGA-2 board to use IRQ12 for interrupts.

Bus Speed...

Some computer systems which were designed after the Radius XGA-2 interface offer extremely fast bus speeds which may be too fast for the XGA-2 design to operate correctly. In this situation, you may also experience errors such as several beeps at startup indicating no video system is installed at all. If your computer offers a way in which to change the bus speed of your computer, you may be able to work around this problem. Your system may offer this as an option via jumpers or dip switches on your computer systems motherboard. Some systems also offer this as an option via a configuration program when your computer first starts up. If this option is only available via a configuration program at startup, you will have to remove the Radius XGA-2 video card and either install another type of VGA card or turn on the built in video system if one is available. Consult your documentation for your computer system for specific details on how to access this option for bus speed if one is available. Once this option is found on your computer system, we recommend configuring the bus speed for 8 MHz operation.

Wait states...

The Radius XGA-2 card in its default configuration does not utilize any wait states, meaning that the card accesses your computer's memory as quickly as your computer's CPU allows it to without waiting. While most of the computers offered today with 486 or higher CPU's do not need the XGA-2 card to utilize wait states, older CPU's may not and then would require that the XGA-2 card utilize its own wait states between memory access. If your system does not start correctly with the Radius XGA-2 card installed and you suspect a wait state problem, try setting this jumper first to introduce 1 wait state and if the problem continues, try setting this jumper to introduce 2 wait states. No more than 2 wait states should be needed and if the problem continues with 2 wait states added, your problem is probably not related to wait states and may be a conflict somewhere else in your configuration.

BIOS Setup...

Some computer systems offer a feature within their setup program to "shadow" the BIOS. What this means is that the basic instruction set for the computer is placed in a more convenient but non-standard place to access system and video memory. If this is done, the Radius XGA-2 video card will not function properly as it may not correctly communicate with the BIOS and visa versa. If you have an option for "shadow" of video or BIOS instructions, we recommend that you disable this feature. If your computer has this feature and it cannot be disabled, your computer may not work correctly and may not be fully compatible with the Radius XGA-2 video card.

Q: After installing the XGA-2 card into my computer when my other cards are installed, I do not get an image on my screen at startup or

my computer does not start at all.

A: First, remove all other expansion cards from the computer and make sure that the Radius XGA-2 video card works with its default settings as outlined in the previous question. Then place each card back into the computer one at a time, restarting the computer after each card is added. When the problem is duplicated and the offending card is found, check the offending expansion cards settings to avoid ROM address space from A000 to C7FF, DMA channel 7, I/O locations 2160 to 216F, and IRQ12. Also, if using a networking interface or SCSI controller card that utilizes bus mastering capabilities, you must disable the bus mastering capabilities of the offending card as the XGA-2 card is also a bus mastering card which cannot be disabled. You may only utilize one bus mastering type expansion card on an ISA type bus.

Next, make sure that you do not have a second VGA or VGA compatible video card installed. If you do, your system will not start correctly with the Radius XGA-2 video card in its default configuration. If you require that the Radius XGA-2 video card and your VGA or VGA compatible video card both be present and active in your computer at the same time, the ROM for the XGA-2 video card must be disabled. To disable the ROM on the XGA-2 video card, you must turn switch 2 on bank SW2 to the off (down) position. This disables the VGA compatibility modes of the Radius XGA-2 video card. If you disable the VGA compatibility of the Radius XGA-2 video card, you must either have a second display connected to the Radius XGA-2 video card or you must utilize a "pass-through" cable between the VGA card and the Radius XGA-2 video card. If utilizing a "pass-through" cable, your display should be connected to the Radius XGA-2 video card. When two video systems are used in this manner, keep in mind that only the Radius XGA-2 video card is used when XGA-2 type video drivers are selected from your application or from Windows and that when the XGA-2 video drivers are being used, the VGA video system will be turned off automatically. If using more than one Radius XGA-2 video card in your computer, make sure that only the first Radius XGA-2 video card has its ROM turned on and disable the ROM on each additional XGA-2 video card installed.

Q: After I install the XGA-2 drivers when starting Microsoft Windows, it either quits automatically to MS-DOS , garbage or no video appears on the screen, or the image on the screen is off center or has vertical or horizontal lines on it. What could be wrong?

A: The Radius XGA-2 video card can operate with a variety of display types and with a variety of timings. The timings that the Radius XGA-2 card offers are determined when the Radius XGA-2 card initializes itself when your computer starts up. Prior to running Microsoft Windows or other MS-DOS applications using XGA-2 drivers, we recommend using the Radius XGA-2 "DMQS" setup program to tell the Radius XGA-2 video card what type of monitor is going to be used with it. "DMQS" is an acronym for Display Mode Query and Set. To run this program, go to the MS-DOS prompt, then go to the XGA$DMQS directory and type SETDMQS. This will give you a listing of a variety of monitor types to choose from. From this listing, select the display which most closely matches the monitor type that you have connected to the Radius XGA-2 video card. If unsure as to what monitor to select from this listing, contact the manufacturer of the monitor for their recommendations as to which monitor selection from this list would work with your monitors timing specification.

Also, make sure that the line which loads the file "SETDMQS.SYS" is present in your CONFIG.SYS file. This line initializes the Radius XGA-2 video cards bus mastering features which are required for proper XGA-2 operation.

Q: Can I use the XGA-2 interface with OS/2 and what drivers do I use?

A: The Radius XGA-2 video card is fully compatible with OS/2 2.1 or higher. The XGA device drivers included with OS/2 2.1 should work fine with the Radius XGA-2 video card. The utilities and drivers included with the Radius XGA-2 video card are designed specifically for MS-DOS and Microsoft Windows 3.1 applications and should not be used with OS/2. If you wish to configure the DMQS selection to a different timing which may be more appropriate for your display type using OS/2, you should open your "System" group, then open your "Display" program, then select "Page 2 of 2". This will give you the complete listing of available display types to use with OS/2. You should select the display which most closely matches the monitor type that you have connected to the Radius XGA-2 video card. If unsure as to what monitor to select from this listing, contact the manufacturer of the monitor for their recommendations as to which monitor selection from this list would work with your monitors timing specification.

If after installing OS/2 2.1 on your system and selecting the XGA graphics system from the installation program you then get garbage or no video on the screen, your display is not compatible with the default DMQS display type that OS/2 uses which is 8514. In this situation, we recommend using a different monitor which is 8514 compatible temporarily to configure OS/2 to then use a DMQS setting more appropriate to your other display type. Once the correct display type is selected from the "Display" program, your other monitor should operate fine when it is connected.

After installing OS/2, you run the Radius XGA-2 video cards diagnostics and will find that the bus mastering test fails. This will happen every time. The diagnostics for the Radius XGA-2 video card were designed specifically for use with MS-DOS.


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