Question games restart when i higher the resolution

[deezlee20]

i recently upgraded my graphics card after the last one seemed to die gtx 970, i have upgraded to a geforce 2060 super oc 8gb, i can play cod in the 1920 x 1080 fine but the minute i increase the resolution the PC just restarts, thinki9ng maybe its a psu problem but would like to now before i buy one , any help would be great, also over games crash when playing in 3840 x 2160
specs:
windows 10 64 bit
intel core i7-6700k
16 gb ram
z170x-gaming gigabyte technology

 

[sizzling]

What is the make and model of your PSU and how old is it? From your description my first thought is psu.

 

[deezlee20]

What is the make and model of your PSU and how old is it? From your description my first thought is psu.

vs 550 crosair had it with pc just over 3 years should i think about getting a new psu?