Hi guys, I have an older DIY Mac Pro and I am running Mavericks. I have recently tried to use a second monitor but the OS doesn't seem to like it. The main monitor is connected by DVI, and the second one is connected by VGA. Looking in System Preferences I cannot see an option in 'Displays' to add an additional monitor. In Mission Control I have unchecked the 'Displays have separate spaces' checkbox. I notice that people on this forum are using multiple monitors who have a Macbook Pro, but is this possible running Mavericks without a laptop?