PC works fine, but then cuts off the power when gaming

[oeglen01]

December last year I started having issues with my PC cutting of the power while gaming. It wasn't even able to boot. I found out that my GPU was the issue here (AMD Radeon HD 6960). I then changed the GPU and bought a GTX 980 TI which consumes less power. But now I have the same problem when gaming. I load the game and play for about 5 minutes, then it just cuts off the power (The PC restarts after a couple of seconds). Don't know if I should check the voltage that the power supply provides..
Hope you can help me!

My PC specs:
HP Z800 Workstation
2 Intel Xeon E5645
96 GB DDR3 Ram
Nvidia GTX 980 Ti
4 1TB HDD
1 128GB SSD

 

[XxDarkMarioxX]

I would suggest posting what power unit you have because that may be the reason why your computer turns off because the PSU is not giving enough power to GPU!

 

[oeglen01]

I would suggest posting what power unit you have because that may be the reason why your computer turns off because the PSU is not giving enough power to GPU!

This is the power supply:
https://support.hp.com/sg-en/product/hp-z800-workstation/3718645/document/c01720139/

The 850 watt version.
I am kinda thinking if I should buy the 1100 watt version?

 

[SgtScream]

I would suggest posting what power unit you have because that may be the reason why your computer turns off because the PSU is not giving enough power to GPU!

This is the power supply:
https://support.hp.com/sg-en/product/hp-z800-workstation/3718645/document/c01720139/

The 850 watt version.
I am kinda thinking if I should buy the 1100 watt version?

More wattage isn't necessary, the defective PSU just needs to be replaced.

 

[oeglen01]

I would suggest posting what power unit you have because that may be the reason why your computer turns off because the PSU is not giving enough power to GPU!

This is the power supply:
https://support.hp.com/sg-en/product/hp-z800-workstation/3718645/document/c01720139/

The 850 watt version.
I am kinda thinking if I should buy the 1100 watt version?

More wattage isn't necessary, the defective PSU just needs to be replaced.

I need an original one though.. Others won't fit.. The original Power supply costs around 400 USD

 

[SgtScream]

Type HP Z800 power supply into eBay.