Hello Rehabman I am now running my computer on Maverick 10.9.0. I have a haswell computer type computer. Also when I plug my HDMI cord into the side of my laptop my laptop now freezes. So I guess with the changes in Maverick they have better graphics support. My video memory now reads 1536MB up from the usually 1024MB. I have some artifacts on the menu tool bar probably due to the higher memory dedicated to graphics on 10.9.0. I am currently time machining my hard drive. So if I have to upgrade I won't have to start completely from scratch. Please take a look at this file and give me your advice. If you can give me some helpful advice I might post another thread in the Maverick section. Also what version of Marerick are you running on your computer? What Kext files are responsible for the HDMI port. I loaded the bare minimum kext files to avoid my computer from locking up and I add kext files one at a time to get things fixed.