Sweet, I just heard, tested, and confirmed that the drivers HP has posted for the TI smartcard reader work for 64-bit even though they are only listed in the category for 32-bit versions of Vista. I am only able to test this on my nc8430 and my nx6125, beyond those two models I have no idea whether this is still the case. This nearly completes my driver set. I still have one item listed as an "unknown device" but I don't know what it could be. Even my fingerprint scanner is working, though I don't use it.
From the site:
This package contains the driver for the Texas Instruments PCI (TI-PCI) 6x12/7x12 Cardbus (Media Card Reader) for the supported notebook models and operating systems.
Source: HP Compaq nc8430 Notebook PC - Texas Instruments Media Card Driver - HP Business Support Center
On a side note, I'll be the first to admit I have some kind of weird fascination with HP. Especially now that they carry the old Compaq form factors. I'm dying to get my hands on their new tablet.