Pulling apart a random old computer the other day that had this mini-PCIe modem card in it. Yes, a dial-up modem, for a mini PCI Express slot. I didn't realize they still made dial-up modems for long enough that they'd go into those.
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@wildweasel I wonder if it works with DSL. That'd explain the anomaly.
@wildweasel Caveat emptor 
@corrupt Having looked up the card in question, evidently not? Seems like this model caps out at 56K V.92 - https://theretroweb.com/expansioncards/s/lsi-concorde-c40