What are the rest of the spcs of your PC?
If it requires 3gb minimum, I wouldn't recommend playing it on only 2gb. You will more then likely see major performance/crashing issues. When a game calls for a minimum amount of any specs, whether it be ram, cpu, gpu, ect, it's always best to have a little more then what it calls for so you have a little more head room for other tasks that may be trying to access those items, like the operating system.