In System Center Virtual Machine Manager, you can create a quota point system to restrict how many VMs your self service users can run at any one time. By using the quota points, you can prevent your users from accidentally, or intentionally creating a Denial-of-Service attack on your host servers.
We all know that virtual machines do not have to be created equally. In other words, they may consume more or less resources than other VMs. For this reason, you can assign a different quota point value to different virtual machines. That way a single user, or group of users will not fire up resource intensive VMs and bring your hosts to their knees.
To do this, open System Center Virtual Machine Manager.
On the menu bar, click Go \ Virtual Machines
Right click the VM that you want to change the default quota point value for. Click Properties
Click the Settings tab.
Notice the default value for the Quota is 1. For VMs that are resource intensive, you may want to increase this number.
Click OK when you are finished.