Depending upon what you're using it for, you might well get away with it, but for some purposes the accumulated sample rate clock drift eventually gets too bad.
You could make a long multitrack recording this way, and so long as you played it back from the start on the same hardware (i.e. so the soundcards would drift relative to one another more-or-less consistently with how they drifted during the recording), the playback might be ok. But if you begin playback half way through the recording, then the timing between channels might be out, as your software has no idea how much drift each channel ought to have accumulated by that point in the recording.
Mind, it's been at least 15 years since I actually put any of this stuff to the test. Tolerances on modern soundcards might be really tight.
You could make a long multitrack recording this way, and so long as you played it back from the start on the same hardware (i.e. so the soundcards would drift relative to one another more-or-less consistently with how they drifted during the recording), the playback might be ok. But if you begin playback half way through the recording, then the timing between channels might be out, as your software has no idea how much drift each channel ought to have accumulated by that point in the recording.
Mind, it's been at least 15 years since I actually put any of this stuff to the test. Tolerances on modern soundcards might be really tight.