Monitor displays 'No source signal'....

[dustyfast]

Hi there,I have a nvidia geforce gt 610 and compaq presario GPU And CPU respectively.
So the problem is when i was playing my Call of Duty MW2 there was a sound like GGLLLLLLLLLLLLLLLLLLLLL!!!!!
and my monitor was displaying a message 'No Source Signal'...
I have a HP 2009f monitor.
2gb ram,Intel Core 2 duo 2.80ghz
windows 7 32 bit
I have checked every wire linked to my monitor and graphics card.
even the cables aren't damaged.Is there a problem with my Graphics card?Or Monitor?Or CPU?
It only happens when i play video games..
Other wise if I play games online nothing happens.i also checked the gpu temerature it is normal 81 C.My GPU mAX. temperature is 120 C..It seems every game i run has this problem..

These are the games i ran;;
Borderlands pre sequel
COD MW2
Skyrim
Turok(2008)
Dead island Riptide
Tales from Borderlands
Games of thrones
Amnesia The dark descent
Burnout Paradise
Even the low graphic games like need for speed most wanted(2005) display the same message after some while..

These games were running smoothly 3 days ago.
and now this error is happening with my monitor and there is also this unusual sound.
I have these games installed for like 6 months and nothing happened.There is no problem with my Wires.

Thank You..

 

[Aefuan]

Your GPU/CPU could be causing that.

Download Furmark and test the GPU with it. Run it for about 20-60 min and check the temperatures. If it doesn't crash then you should test the CPU with Prime95 and also check it's temperatures on idle/load.

Which PSU are you using?