This topic is a copy paste from Techrepublic, written by Rick Vanover.
Group Policy is a great way to deploy settings to users and computers centrally — unless you wind up waiting for the updates. The default interval to update the Group Policy to a computer account is 90 minutes; further, there is an offset of 0-30 minutes. While this schedule is fine for most situations, there may be times when you need to make it shorter for quick updates.
There are various ways to shorten the Group Policy refresh interval. But be careful when you make these changes because it will increase the traffic from domain controllers to computer accounts.
One approach is to have the server computer accounts receive a tighter refresh policy, with the assumption that there are fewer servers than client computers. The refresh interval is defined in Group Policy in the Policies | Administrative Templates | System | Group Policy section in a value called Group Policy Refresh For Computers (Figure A). After the Group Policy Refresh For Computers value is selected, it is represented in minutes that will determine how frequently the computer accounts will try to update the policy.
Figure A
Another option is the offset labeled Random Time Added. The offset is  important because it ensures that the domain controllers don’t get  perpetually bamboozled with request for updates. Figure B has a tightened value for the update refresh interval.
Figure B
A good approach is to tighten the update interval when a number of  frequent changes need to be deployed, such as after a move or a major  system update. But consider whether a tighter interval is needed,  especially because in most cases the updates do not retrieve a new  configuration for the computer account. On the other hand, large  environments may want to make this interval much larger when thousands  of computer accounts may be in use.