refer to the Boot Camp documentation for which key to press.
I believe it is the Option key, held down at startup
P
I installed windows 7 on my mac pro mc516lla. The installation is working very nicely, only problem is once you start in windows, pc will continue to use windows as default OS (same applies for mac also). Is it possible by any means that while starting both the options will be displayed during startup and the OS which needed for that session can be directly selected without entering the default OS and bootcamp?

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