There is no reason that LE4 will not work with any soundcard, providing you have the correct ASIO drivers.
What you do need to know is that Cubase will use only one ASIO driver at a time, eg if you're using the Omega driver, you can't route Cubase audio through the onboard soundcard and vice versa.
You can use 3rd party drivers such as Asio4all (google this) to drive multiple audio devices but it can be a little hit and miss.
If you don't mind my asking, I'm curious to know why you want to run an external Soundblaster card as well as the Omega in Cubase.
Cubase LE1.08, Tascam US144, Vista HP 32bit, Toshiba Satellite.
"If music be the food of love, play on" - Shakespeare
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