My Pc goes to Sleep mode when i play GTA 5

[sun204]

My New PC Specs as follows :
Processor : Intel Core i7 6700 @ 3.4 Ghz
Ram : Corsair Vengeance 8Gb x 2=16Gb
Motherboard : Asus Maximus VIII Hero
Graphic Card : Asus Strix GTX 970 OC Edition
Os : Windows 10 Home ( Activated Original )
SMPS : Corsair TX650
Cabinet : Cooler Master K380
Fans : Only one that's comes installed in the cabinet . Will increase two more fans soon .
Monitor : HP 2311f Using it on DVI port . Hdmi didn't work

No cpu cooler installed as don't want to over clock

I am playing GTA 5 on Geforce optimised settings

When is start playing GTA 5 its works well for 15-20 min then suddenly the screen go off to sleep mode and then it doesn't start up although the pc is working fully . Then have to restart the pc . If I turn off the monitor and turn on it again then its shows no signal . What is the problem ? Please help me .

 

[Petrossa]

No cpu cooler at all???

 

[superg05]

My New PC Specs as follows :
Processor : Intel Core i7 6700 @ 3.4 Ghz
Ram : Corsair Vengeance 8Gb x 2=16Gb
Motherboard : Asus Maximus VIII Hero
Graphic Card : Asus Strix GTX 970 OC Edition
Os : Windows 10 Home ( Activated Original )
SMPS : Corsair TX650
Cabinet : Cooler Master K380
Fans : Only one that's comes installed in the cabinet . Will increase two more fans soon .
Monitor : HP 2311f Using it on DVI port . Hdmi didn't work

No cpu cooler installed as don't want to over clock

I am playing GTA 5 on Geforce optimised settings

When is start playing GTA 5 its works well for 15-20 min then suddenly the screen go off to sleep mode and then it doesn't start up although the pc is working fully . Then have to restart the pc . If I turn off the monitor and turn on it again then its shows no signal . What is the problem ? Please help me .

i really hope you didn't or don't fry your cpu you must always use a cooler overclocking or not you cpu probably got to hot and shut itself off so it could limit the damage