Macbook Air dramatically slow on OSX and run fine on Windows

I am experiencing a problem since few days. After a crash on OSX (Yosemite), I have switched off the Mac, then trying to switch it back on without success (Apple logo with progress bar seemed to be frozen after few minutes).

Finally, after a NVRAM reset, I could boot MacOS X but, it was dramatically slow. After checking and repairing disk authorizations, and checking disk error, nothing went better.

So I decided to give a try on Windows, so, reformatted the SSD and installed Windows 8.1. Had no issue on Windows, everything was working fine without any lag. Then, I tried installing back Mac OS X with the remote installation solution (cmd + option + R at boot). The installation wizard was again dramatically slow, and after complete SSD format again and installation, I have MacOS X Lion lagging and slow.

I had made a check of the RAM using Windows Memory Diagnostic Tool, checked the processor using Intel Processor Diagnostic Tool and SSD using Apple Disk Utility. I have no error or crash on MacOS X, just the OS running slow, even the mouse speed is changing…

MacOS X seems to work fine for about 10 seconds after waking up from sleep mode, then, fan is switching on directly after, even if the computer is cold and computer become slow again.

So, I wonder if this is a hardware problem and what can provoke that.