No version of AppleShare File Server or Print Server is supported on computers equipped with either the Power Macintosh Upgrade Card or the Macintosh Processor Upgrade. Although the software may run without crashing, it is untested and therefore, unsupported.
There is little to be gained by running a server on a system with an upgrade card since all the upgrade card does is increase the processor's power. The server is heavily dependent on the I/O subsystems, which are unchanged, and therefore the performance increase is not significant.