My Pc keeps powering off (full shut down straight to black screen) when I play games HELP

[bloxcastclayton]

Pc specs:
CPU: i5 4690k 3.5Ghz Turbo Boost enabled
GPU: Gtx 1080
RAM: 8gb ddr3 x2
PSU: Thermaltake tr2 challenger 500w
GPU and CPU are at safe temperatures with my GPU maxing out at 71 degrees and my CPU at 59-63 depends on game
Also I am building a super budget gaming PC for my fathers house is this a good spec for it? I don't want to spend much more than this:
CPU: i5 2300
GPU: Gtx 670 2gb
RAM: 4gb x2
Motherboard: lga 1155 from ebay
PSU: evga 500 w
Case: Have an old Acer one use that if got no money left otherwise get one
HHD: 320gb amd 120gb from my PC
Please answer first question first though please

 

[jankerson]

Your PSU s complete garage, JUNK, one of the very worst PSU's made.

You need to get a higher grade unit.

Min of a Corsair CX550M.

 

[DigitalHamster]

As jankerson said above, your PSU needs to be upgraded.
What is happening is that it is being pushed pretty hard, and the over temperature protection is kicking in.
When this happens, the PSU suddenly switches off and that explains the sudden black screen.

The only option is to replace it with a better power supply.
I would look at any reliable models of at least 550w, by brands such as Corsair, Seasonic, EVGA, Aerocool etc.
Check the reviews of any models you are thinking of buying to make sure they do well when their performance is tested - a good place to check is here on Tom's or Johnny Guru.