This issue has been present since purchase (October 2013). But it has progressively become worse. It takes around 2 minutes to boot up and can't really multitask well (e.g. it stutters). General use is painfully slow. I have called Apple and troubleshooted the problem. Their final suggestion was to delete everything on the hard drive and clean install. This is an arduous task and not something the end user should have to do. Logging on yesterday, a message saying "run out of application memory did not go away". There were no apps apart from finder running. Does this sound like a hardware or software issue? I have already reinstalled the OS (not clean install). Computer specs: 27" Late 2013 iMac, 1TB harddrive, 16GB RAM.