Problem:
A few days ago I had a crash in Windows 8. It was just freezing content by a little bit until the only thing that could move was the mouse pointer. I instantly got an idea it was something wrong with my system drive because it still did show contents loaded into memory. I rebooted the machine and suddenly got a BSOD (or a similar thing) stating that I have to repair my pc.
After numerous restarts it did not come back, but after complete power cycle it did. But not for long, just until I fired up my browser and opened some websites - and it crashed the same way again.
I have a dual boot Windows Server (for education purposes) which is on another drive. Tried booting into that - everything's okay. But until I tried to write or copy something to the drive. It instantly become laggy, the My Computer is very slow and after a while it loaded, but the drive icon no longer showed the capacity bar and you could not open the drive.
Then, after a reboot, I tried some programs that show SMART information for a drive - all the parameters are excellent.
I tried connecting to different SATA port on the motherboard, replacing SATA cable, plugging another power connector. The voltages on the PSU are fine. I even tried a different PC. So the problem is in the drive.
Questions:
What can be wrong with it? What is the best way to restore my personal data from the drive or even make a whole image of the drive in this situation? I don't want to try anything stupid as it can stop working at all and I'll lose my data.
Hardware:
Motherboard: ASUS P8Z77