Windows Service Multi Core Utilisation

We have an number of old visual C++ 6 windows services that are currently runn开发者_运维百科ing on a single server. The problem seems to be that all of the service seem to utilise only a single core. (There are 4 cores)

Isn't the multi core utilisation (on windows server 2003) supposed to be optimised by the OS?

Nope. As long as each service is single threaded (or uses a single process) all the OS can do is to assign to each service a different core to run it in parallel to the rest of the services. The OS can't parallelize a single thread of execution.