alt Hacker NewsISA slots were definitely rather rare on motherboards by the time you got to the Pentium 4 era, so that's cool that you managed to find one that also offered DMA, since I believe Sound Blaster cards needed that to properly function.
I think I would have done the same with my AWE64 Gold if that was still an option for me in the early 2000s.
Having googled it a bit now, it's fully possible I have my wires crossed, since I know that P4 machine had the SiS 645 chipset which of course had built in audio.
I definitely used the Sound Blaster with my 486DX100, and I recalled migrating it to at least one other machine after that; it was nice for the joystick port and also the better wavetable synth on classic games.