Macbook pro still slow after erase

Question

Hi everyone,
I have a slow performance problem on my macbook pro that I cannot solve. I tried already everything I could find here (see below) but nothing worked so far and that´s why I´m posting a new thread.
PROBLEM: Macbook got suddenly incredibly slow.
Start up takes up to 10 minutes (around 7 min for booting to log in, another 3 min before I can open any app). Shut down is faster but takes still longer than it used to. Moreover any single click takes ages while using the machine and I constantly get spinning beach balls even if I just check drop-down menus. Basically any operation takes ages now and I cannot work properly. Also audio stream from iTunes is not fluid and I get audio interruptions quite often. All of this was a sudden change: my macbook pro was always working fast and good. I cannot track back the start of this behavior to any update, installation or particular event. I don´t use my computer very often, do not install any crap, and only 200 GB or so were occupied on the disk.
WHAT I HAVE TRIED ALREADY:
- Checking activity monitor: nothing seems to be wrong here
- Utility Disk: SMART status of HDD is ok. Verified disk and permissions and repaired whatever had to be repaired (apparently only some permissions)
- Restarted in safe mode and then normally booted
- Reset PRAM
- Reinstalling Mavericks
- Went to an authorized store where they did an hardware check, said everything looked fine and suggested erase+fresh install
- Erased disk (after a complete backup) and did a fresh Mavericks install
None of this has worked. I now have a Macbook pro that should be as new but problem remained the same.
SYSTEM:
Macbook pro 13´ from 2012
OS X Mavericks
HDD 750 GB
RAM 8 GB
(let me know if more information is needed)
Some have suggested upgrading the RAM or the HDD or to change the HDD but I cannot believe the system all of a sudden needs more power (given that I don´t use it that much and it´s just two years old) or that the HDD fails after just 2 years!!
After weeks of struggling I am a bit frustrated and I hope someone can help.
Thank you

Answer 1

Launch the Console application in any of the following ways:
☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
☞ Open LaunchPad. Click Utilities, then Console in the icon grid.
The title of the Console window should be All Messages. If it isn't, select
          SYSTEM LOG QUERIES ▹ All Messages
from the log list on the left. If you don't see that list, select
          View ▹ Show Log List
from the menu bar at the top of the screen. Click the Clear Display icon in the toolbar. Then take one of the actions that you're having trouble with. Select any messages that appear in the Console window. Copy them to the Clipboard by pressing the key combination command-C. Paste into a reply to this message by pressing command-V.
The log contains a vast amount of information, almost all of which is irrelevant to solving any particular problem. When posting a log extract, be selective. A few dozen lines are almost always more than enough.
Please don't indiscriminately dump thousands of lines from the log into this discussion.
Please don't post screenshots of log messages—post the text.
Some private information, such as your name, may appear in the log. Anonymize before posting.