Trying to use target display mode on my iMac.
I've just bought Mini DisplayPort to Mini Display Port cable to use my 21'' iMac (mid 2010) as a second monitor for my 15'' MacBook Pro (mid 2009).
Both machine is running OS X 10.9 and don't have ThunderBolt port.
I tried to enable target display mode (cmd +F2) on my iMac and nothing was happen. What I need to do?
iMac, OS X Mavericks (10.9)