Hello! I already posted my problem on Apple discussions but didn't get any answers. So I'll give it a try here. A week ago my MBP decided to get extremely slow and freeze. I had to turn it off the hard way (power button) and when I started it again it showed me the Apple logo/slashed circle/directory icon with a question mark. After a lot of trying I decided to send my SSD back and get a new one. In the meantime I still need my laptop so I built the original hard drive back in (OS X was still installed). Now it ran okay, slow-ish like a 3200rpm hard drive runs. After a day or so it began to act up and I decided to do a clean install because I wanted to do that anyways. That took literally 6 hours. Even after the clean install it's horrible slow. When I type something in non-native OS X applications (Firefox, Twitter,...) it freezes for a few seconds. Even when I click on something in Finder it freezes. It only freezes the application where I type or clicked, so not the whole system. Oh! Sometimes (!) when I have to restart it shows the slashes circle + Apple logo but starts normally or it boots into recovery mode. Resetting PRAM resolves that but it's still weird. I googled a lot and tried even more. Here is what I tried so far: Made a new user account - worked for 5 minutes Double checked if the drive was connected right - it was Ran Apple's extended hardware test - no errors PRAM reset - did nothing SCM reset - did nothing either In Disk Utility: check/repair disk - no errors Disk Utility: check/repair permissions - repaired some but didn't help at all SMART Utility - no errors Specs (+ some extra information): Macbook Pro 13" (mid 2012) i7 2.9GHz - average 90% inactive 8GB RAM - average 3GB used most of the time 750GB hard drive - 22GB used OS X 10.8.4 All updates installed I might have to say that it doesn't freeze always but more like 90% of the time. It's really confusing and irritating me. Anybody suggestions?