Service Virtualization can perform volume or load testing but not environments have the capacity for the load.
 

Can we use our existing DevTest environment to perform volume testing?
If a new environment is needed, what type of server (cpu, memory, etc...) is needed?

All supported versions of DevTest

There are many factors that determine the amount of load any given environment can handle. 
Example: 
Request/Response size 
Available memory for client(s) and server(s). 
Available cpu for client(s) and server(s). 
Other applications running on the client(s) and server(s).
Network latency. 
Available network bandwidth. 
Antivirus or other network scans 

Because of the above, it is impossible for support to provide details about performance testing. Generally, CA Services can assist in determining and adjusting load performance testing. However, some general help can be found by searching the correct version of documentation for: 
Load and Performance Server Sizing 
Sample Performance Benchmarks for Basic Service Virtualization

If you need assistance in contacting CA Services or would like to discuss general guidelines, please open a support ticket.