Before you go through the hassle of getting a new ROM for your GVP board, you can use a soft ROM from Ralph Babel's website (
http://www.babel.de). With GVP autoboot disabled, just drop the driver into SYS:Expansion and your GVP board should hopefully work just as before - minus autoboot, of course.
If that works, then you can go ahead with getting a new ROM. I think TJLazer here at Amiga.org sells them.
If that doesn't work, then maybe even the latest GVP ROM is buggy with 060/Blizzard boards. In which case, you should probably transfer your GVP board to another machine, keep it for an emergency, or sell it on. SCSI performance on the Blizzard will be much better.
