directX 9b OPK/ DX9b redist

[kC_]

hi.. i added nerovision express too my unatended dvd today..... but as it started installing, up popped the message "you must have DX9.0a or newer installed too instal Nerovision express"

now, i thought DX9b was already being installed by the svcpack and DX9NTopk.exe during t-13 of windows setup, its in my i386/Update folder and DX9NTopk.exe with no switches, is first on the list in svcpack..

but its obviously not working...

i have a DX9b redist which i could include, but when i was following the guide @ http://unattended.msfn.org/ it said its best too use the DX9NTopk.exe as it doesnt require any switches...

the dx9b redist i have has these files..

BDA.cab
BDANT.cab
BDAXP.cab
DirectX.cab
DSETUP.dll
dsetup32.dll
dxnt.cab
dxsetup.exe
ManagedDX.CAB
mdxredist.msi

is it possible for the redist too be ran in svcpack/update method ?

or must it go in my start.cmd file?

e.g

ECHO.
ECHO Installing DX9b redist
ECHO Please wait...
start /wait %systemdrive%\install\dxsetup.exe

whichever method, whats the exact switches i need so its silent, and doesnt reboot.....

and what the hell is tthat dx9ntopk.exe if its not dx9 ?

thanks for any help