No, nothing you rally can do about the performance degradation other than faster disks in the server and more bandwidth to the network from the server. In windows 2003 each computer that connects to the WDS is a unicast or one to one connection. Each additional connection will degrade the performance of all. I find that with a 1gb connection from the server I can get five or so simulatneous images done in an hour and a half or so. More than that and it gets pretty slow. One thing to try is to stagger the image process somewhat so they aren't all trying to do the same thing at exactly the same time. I've had better success doing it that way. If you have WDS installed on a 2008 server, then you could enable multi-casting which would allow you to image multiple systems with little performance degradation.