A friend's computer was infected with the Black Ice virus. Symantec and Sophos say that it is memory resident. How do you clean memory resident viruses?
For the longest time, the safest way to handle any virus was to power down your system and restart it using a clean boot diskette. This would ensure that any viruses which remain memory resident would not have a chance to load themselves into memory and could be cleaned with little trouble. The problem that is posed by this approach arises when dealing with operating systems which do not make it easy to do this sort of operation -- Windows NT, 2000 and XP, for example.
Have you tried cleaning the virus using the AV products you have? Most modern AV products can also handle viruses which are residing in memory. They also usually offer you the option on installation to create clean boot diskette(s).