Hello flashrom List !
This is reporting success reading (dumping) the ROM BIOS on my IBM Aptiva 2170-G (actually an ACER V75-M motherboard). This MoBo has the SiS 5595 southbridge, which per flashrom issued warning had been untested.
I have /not/ tried to write or erase, sorry; though have little doubts those operations would succeed similarly.
Many thanks go to the developers!