I have been using Revit 2013 on my laptop for the last few weeks as I have been travelling but now I have put it on my workstation the rendering speed has considerably slowed down despite my workstation being a faster machine. The laptop is running windows 7 and the worksation XP could this account for the difernece
The laptop is running windows 7 and the worksation XP could this account for the difernece
That would be my first guess. Also your video card on the desktop may be part of the issue.
Video card do not impact MentalRay rendering times, but can affect iRay rendering performance.
I doubt the op is referring to the iRay performance, this can have another causes.
A simple test can be: close all other views, save the project, exits Revit, and open again, than do a render to measure the times.