HP Vectra XU5 Reference Manual page 45

I/O Addresses Used by the System
1F0h–1F7h Hard Disk Controller 1
278h–27Fh Parallel Port 2
2E8h–2EFh Serial Port 4
2F8h–2FFh Serial Port 2
378h–37Ah Parallel Port 1
398h–399h Integrated I/O Controller
3B0h–3DFh Video Adapter
3E8h–3EFh Serial Port 3
3F0h–3F7h Primary Flexible Disk Drive Controller
3F8h–3F7h Serial Port 1
Refer to "HP BIOS I/O Port Map" for more detailed information.
Vectra XU Technical Reference Summary of the HP BIOS 45