If you have bought one of these cards and it is working well or poorly for you, in whatever machine you have it installed, we would really like to hear about it . If it is working well for you try doing as many reboots as you can stand to see if your machine freezes. If it is working poorly and you have a device connected to the serial port, try disconnecting it and see if that clears up the problem. On our recommendation Sonnet connected an Epson printer to their machine and was able to reproduce the boot crashing we have experienced confirming that this is a common problem with these cards rather than an isolated one. Our advice is to hold off buying one of the Sonnet cards until the problems with them have been identified completely and fixed.
Sonnet is in the process of trying to resolve the issue.