Couple of options. What about IRQ 7 / LPT1?

The IRQ can be shared, but you will hear sounds when you print if I recall correctly.

What exact card? What OS? What machine?

LPT1 is on IRQ7. It's bidirectional, so I'd like to keep that one.

Hearing sounds when I print isn't a big deal. I'm not going to be printing while playing DOOM of course. I may just leave well enough alone if that's the only symptom of a conflict. I have also noticed that once in a while on a warm reboot LPT2 will not appear in the BIOS. Again, not a big deal.

The PC is a generic 486 VLB board with AMI bios, and the I/O card is this one. I can't find any identifiying information, but I got a card with jumper settings on it in the box. LPTs can only be assigned to 5 or 7.

Often the jumpers let you disable the printer port. Worth checking out?

I had a scanner and printer attached to my 486 back in the day, so we had an additional LPT card installed in the PC. One was IRQ5 and the other was IRQ7.
We had a sound blaster 16 on IRQ5.

Gaming was fine, never had a problem. When we went to print something though we would get crackling noises through the sound blaster. A minor annoyance but hardly a big problem.

It's not very common that software uses the IRQ of a printer port. But if it does you may run into a problem.