Ralf is correct, there is no hard limit. If you need more memory than is available for 32-bit java you will need to run a 64-bit browser and 64-bit Java. I assisted a customer with this when they needed about 20 RDP sessions to be kept open constantly, and the normal memory allocation was not sufficient. You can specify the additional memory to be used in the Runtime Parameters field in the Java configuration. You will see this in the Java Control Panel, by clicking the View button on the Java tab. You can then specify the amount of memory to be used. Here is an example setting the memory to be used to 1Mb: -Xms1024 -Xmx1024. The maximum for 32-bit Java is 1200. The customer I referred to set each of these parameters to 3000, 3Mb. Be careful about copying the string I provided and pasting it into the field. I've seen the hyphen changed to a long dash by doing this. The parameter will not work if that happens.