We have not tested, nor do we recommend recording CDs on NT Server in any configuration. It is best to run GEAR on NT 4.0 Workstation.
Large documents being spooled to the server's printer queue can be devastating to a write.
Also, in the 'Server' service in NT 4.0, you can specify how the system is 'optimized', whether it will spend more of the CPU serving files to others, or whether the console should take precedence, etc. It will most likely not be fast enough. Also, if you are on an NT server, it may be difficult to write at 4x at all due to client access. Gear doesn't seem to work at all if the virtual memory isn't about 1MB larger than what NT wants. Also Gear doesn't seem to work very well with less than 20MB of available memory.