Sudden Restart, then an only fan spinning for 30s, then POST

[crosscreakz]

Specs:
Mobo, GIGABYTE GA-B75M-HD3
CPU, Intel i5 3330 3.0 GHz
RAM, Kingston HyperX 2x4GB DDR3
VGA, Zotac GeForce 1050 Ti 4GB
PSU, Dazumba 80plus 600W
SSHD, Seagate Firecuda 1TB


This happened two times when I was playing games. Also happened once when I'm just browsing the internet.


First, when I was playing Witcher 3, then my PC just restarts. After that, I thought it wouldn't POST. I was just 'sighing' and didn't turn off my PC the hard way. Then, after waiting for like 30 seconds, it suddenly POST and brought me to the BIOS menu that has 3 options of:
- Load optimize default then boot
- Load optimize default then reboot
- Enter setup
The choices are something like that. Then, I chose the 'enter setup' and check if anything's change, then I change nothing then Save and Exit Setup.

Play for a long time, for like from 4 PM to 1 AM (for about 9 hours). Then, I went to sleep, turn off the computer safely.

For the next day, I played Ori and the Blind Forest for about 1 hour, then... it happened again. My PC suddenly restart, waiting for 20 seconds then it POST and boot, but brought me to the BIOS menu again like before.
After like only 5 minutes, it restarted again.
Now, sometimes it POST, sometimes it didn't. Even if it does POST, it only brought me to the BIOS menu, and after like 3 minutes, it restarted again.

Now, I'm posting this from my laptop.

Please, any help or suggestion I would really appreciate.
Thanks.

 

[crosscreakz]

Oh, I'm new to this forum. My first post too. Sorry if the writing is that bad.

I have read some posts, there is one that mention the standoffs.
There is actually a problem in my case. Some standoffs are just loss, so the screw keep spinning and can't get fixed in inside the standoff/hole. Is this the problem?
If it is, do you guys have any ideas of what should I do?
I don't wanna really spend a huge money again, I mean, I don't want to buy a case.
Is there any idea to make the standoffs good again? I don't have much idea for this.

Thank you so much.