ASUS 3DP-V500TX
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V. RESTRICTIONS
Restrictions & Trouble Shooting
PCI BIOS
Some PCI BIOS may not assign correct physical addresses to PCI regions. Experi-
ence shows that this sometimes happens with the PCI region for the framebuffer. If
this problem does arise, the NT driver will boot but black areas will be seen on the
screen. If this happens then a new physical address can be configured for the
framebuffer by setting a registry variable. If this variable exists its value will over-
ride any address set up by the PCI BIOS.
If having booted the NT driver, black areas are seen on the screen, try setting this
override variable as follows:
1. run regedt32.exe
2. open the key
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\glint\Device0
3. From the Edit menu choose the “Add New Value” option.
4. Set the Value Name to be “PhysicalAddress.Region2”. Be careful to spell the
name exactly as specified – it is case sensitive.
5. Set the data type to be “REG_DWORD” and press OK.
6. In the DWORD editor window set the physical address value (see below for
suggestions) and press OK.
7. Check that the entry has been created correctly and reboot the machine.
Selecting physical addresses in this way is an empirical task. An address must be
chosen which does not conflict with any other in the system (the PCI address space
is 4 GigaBytes in size so there is plenty to choose from). This task should be per-
formed by the PCI BIOS but if it fails to do this the user must choose instead. A
useful address to start with for the framebuffer is 0xA0000000. If this fails incre-
ment the address in units of 32MB. Another good starting address is 0x40000000.
The final address chosen must be on a 32MB boundary.
On MIPS machines physical addresses should have the top 4 bits set to zero. To
ensure this for the whole region the address chosen should be less than or equal to
0x08000000.
Having created the Region2 registry variable and assigned it a value the machine
should be rebooted. Continue modifying the address until the black areas of the
screen do not appear. Normally, this will work after the first one or two addresses.
Note, this procedure is required very rarely. Generally, the user will never be re-
quired to perform these steps.
V
. RESTRICTIONS
PCI BIOS
