Problem with SSD/HDD or both - freezes

My notebook started getting the occasional "Your PC ran into problems :(" messages after i upgraded to Windows 8.1. I ignored them. 3 days back the notebook just froze - the mouse would not move. I waited for 2 mins and then pressed the on/off button to reboot. The same thing happened twice that day. The next day, the freeze happened but this time the mouse was moving - but there was no action when i pressed the buttons. Keyboard wasn't responding either. I noticed then that the disk access LED was not blinking at all. i rebooted. The problem repeated again in 2 mins - no disk LED blinking and all frozen. This time I rebooted and backed up my data first. Then i read about the SSD/HDD and Intel Rapid Storage (IRST) stuff.

I rebooted the machine several times to find out when/why the probem happens. I have now narrowed it down to the following:

- when i boot, the laptop starts fast.

- IRST shows both SSD and HDD

- a few moments after, either when i have clicked the browser icon or otherwise, the laptop freezes, disk LED not blinking

- if i wait patiently for 3-4 minutes, the laptop miraculously wakes up

- IRST shows only HDD present (screenshot attached)

- after that the laptop runs perfect.

Thinking that this could be a result of Win8.1 upgrade, I have rolled back to the factory settings of the UX32VD like I bought it 2 yrs back. The problem continues.

The problem is repeatable easily.

Is this related to the SSD or the HDD or neither? Please guide. Thanks much!