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Chapter 3: Onboard Graphics Adapter
3. Onboard Graphics Adapter
Each VWP-2040, VWP-2090, or VWP-2110 shipped by Black Box is custom built. If cards are not pre-installed,
then you will need to install the software. For information on software installation, consult the softwaremanual
on blackbox.com.
If you ordered Video Wall Control Software (VWS-2001), this will be installed before the VWP ships.
3.1 Video Graphics Card BIOS (VWP-2090 or VWP-2110)
The Intel x86 based architecture limits the amount of legacy I/O space available in a system to 64 KB. Hardware
that requires I/O access can be mapped into this 64 KB area. A Video Graphics Card (VGC-HDMI-2-4 or
VGC-HDMI-2K-4) requests 256 Bytes of legacy I/O. Any PCIe bridge will align this to a 4 KB boundary, so the I/O
space allocated to each Video Graphics Card is actually 4 KB.
64 KB divided by 4 kB gives an absolute maximum of 16 Video Graphics Cards. Other system devices also
require legacy I/O. Often, the Network Devices will request some I/O space, and so might the USB devices and
on-board graphics. I/O space might only be available for only 8 Video Graphics Cards when installing them in a
complex server class motherboard.
There are a number of different BIOS types in operation as the computer boots. The “System BIOS” is resident
on the motherboard and is responsible for starting up all the hardware and mapping the resources (like the I/O)
so that they are available to the CPU. The “Video BIOS” is resident on the graphics cards. It boots the CPU and
informs the System BIOS which resources will be required for the CPU to operate correctly.
The System BIOS requires an I/O enabled Video Graphics Card if it is used as the boot device, i.e. it provides the
graphics output that displays the BIOS boot messages. The Windows driver for the Video Graphics Card was
designed so that it does not require I/O. We can use two types of Video BIOS for the Video Graphics Card, one
that requests I/O (and that can be used as a boot device) and one that does not. This allows us to increase the
number of Video Graphics Cards that can be used in a system.
To find out more about how to choose the correct BIOS for your requirements and how to update the BIOS for
the Video Graphics Card, see Section 3.2.
