What ups do i need.

[taki tsan]

System is: i7 4790k, GTX970, 8GB ram and thermaltake 730watt 80+ psu

 

[loki1944]

You shouldn't be pulling more than 450W even if you overclock, so I'd get this one https://www.amazon.com/gp/product/B00NWRO7O8/ref=oh_aui_detailpage_o01_s00?ie=UTF8&th=1

I have the 900W version for two of my computers.

 

[taki tsan]

You shouldn't be pulling more than 450W even if you overclock, so I'd get this one https://www.amazon.com/gp/product/B00NWRO7O8/ref=oh_aui_detailpage_o01_s00?ie=UTF8&th=1

I have the 900W version for two of my computers.

are you sure that 850VA will be enough?

 

[loki1944]

You shouldn't be pulling more than 450W even if you overclock, so I'd get this one https://www.amazon.com/gp/product/B00NWRO7O8/ref=oh_aui_detailpage_o01_s00?ie=UTF8&th=1

I have the 900W version for two of my computers.

are you sure that 850VA will be enough?

Yes. http://www.howtogeek.com/161479/how-to-select-a-battery-backup-for-your-computer/