TBH I think you're right about it being a GPU/PSU issue.
I was just trying to rule out other causes.

Okay. I try out a game Nfs Rivals. Ultra settings. After i did it i will write it what happen. Anyway i hope its not the GPu . i donw want buy an expensive one.....

I tried it....
and restart as the same i played NFS Rivals on Ultra ( i can play with it, i did it and there was nothing) but now restart....

After the system is on the game work but about 1-2 hours running the pc the pc restart maybe too much heat on the GPU or PSU????
So what guys do you think????

I used to get this issue with Nfs the run it would plat for 30 minutes on ultra and freeze. i later found out that it was too much stress on my cpu due to overheating..

Your gpu is safe bro it might be psu overheating and it just shuts down on you.. check the power label on there and make sure you have enough power for the whole system.

Other games did it too...
MGS V
Heroes V
The sims 4.....
I check the cabels on the PSU

Can you try with a different more powerful PSU?

or as someone mentioned it before, add some new thermal paste to your cpu to keep it cool (It shouldn't need replacing, but worth a go), or clean out your fans/ heatsink or run more cooling to see if the same issues comes up. (I went with liquid cooling and never looked back)

Maybe even install MSI Afterburner to monitor your temps in game to see whats spiking
https://gaming.msi.com/features/afterburner

Good luck with it!

Thanks J_Hui but i cant do because myfriends has a less powerful PSU.
I have to buy a new one to try out. I clean it out and i will try to repaste the CPU and the GPU. After i will wirte it down what happened .......