monitor goes off randomly

[Henric007]

hey guys , i have been facing this strange issue since a couple of months.
my pc monitor randomly shuts down display whenever i do some work but the cpu is still
running.
i can keep the pc idle for as long as i want without any issues. it seems to be going

off when it gets loaded but i am not sure yet.the temperature has never gone beyond 65 c

unless i do a stress test .whenenver the display goes off the hdd led doesnt seem to be

blinking anymore. it turns off too.
all my fans will still be running(case fan ,processor fan, and psu fan)
motherboard led will still be on, indicating it has not shut down
the only change i notice is hdd led turns off and display goes off completely,but led in the
monitor will still be blinking.

i have never got any error messages ,warnings or blue screen
Currently i am not using using a ups. So probabaly the voltage fluctuations and unexpected power loss might have damaged one of the components



my specs

intel pentium e5700 cpu 3.00 ghz
2gb ram
500 gb hdd
asus p5g41t mlx motherboard
zebronics 450w power supply
windows 7


things i have tried

i tried reapplying the thermal paste and cleaning the whole case from all the dust
i have monitored my cpu temps and so far it looks safe. it never goes beyond 71 degree

celsius.however idle temperature looks a little high. its 40 c

tried stress testing using intel burn test and cpu is pretty stable.
tried cleaning ram and changing slot
windows memory diagnostics showed no error
visually checked motherboard for any leaking or damaged capacitors and everything is fine

display goes off even if sidepanel is removed. moreover i have done almost everything to

prevent overheating. so perhaps its not an issue with overheating processor

 

[Henric007]

Anyone there?

 

[adiec]

have you tried a different psu ? sounds to me like it is having trouble powering everything @ load . when it's not being asked to do very much it is not finding a problem.. but as soon as you ask it for more power .. it's downing tools.

 

[Henric007]

@adiec i too doubted it could be the psu. But when the monitor turns off, everything else still recieves power. All fans still running, mobo led stil on. So i am little confused and btw i havent tested another psu. Is there any way to diagnose my existing psu?

 

[adiec]

are you using onboard gpu .. or do you have a graphics card ? if you're using onboard graphics then my theory behind the blank display may not be a valid point .

the only way to properly test the psu would be to either try it another computer and/or try a different psu in your computer .