PC not booting ...behaving strange.

Hi friends. ..

Its been two days my pc gone mad. I properly played that night..but when tried to start yesterday morning ...it did not beep (bios post), no monitor display, all fans working as should. Didn't boot.
I checked ram, cleaned, swapped slots, tried single channel in both slots, even checked with friends ram....but it didn't boot.
After that ( A.C. power outage) , I tried to boot on home inverter power...I it worked like butter...played game to check if every thing fine.. it worked as normal.
Again when power swiched to A.C. , it booted in 3-4 attempts but as soon I entered user account password I restarted automatically. ... since then it doing same with A.C. power ...one or two times I also reached till desktop but tried to do any process ...it gets off and restart.....
I open everything ... cleaned whole cabinet. ..heatsink. ..applied new thermal paste...reconnected again...but still problem exists as such.
Its not working with A.C. power but fine and performing on inverter power. .
Wth is this..beyond my approch...anyone try to solve this.....

My config...

C2d e7500 @2.93GHz on ASUS p5klam-ps mobo
2GB single ch ram
HD 6790
Corsair GS600

Try using some other PSU.

Mostly PSU issue,try other psu to test.

Ok...but how it works on inverter supply....on inverter it just normal. ..tried gaming also..

Update : if I leave it some time after pressing power button ...it gives beep error ...after that if I plug off and plug in power again ...it boot ...bot only in safe mode it is stable. On normal it get restarted after login screer or if anyhow logged in then it restart by doing any process like refresh or right click.

Update : system started to boot but putting any load like game...hd movie or any software it goes black and restart automatically. . What this means ?? PSU or something different ?

Confirming that cpu temp are normal.

how old is psu and what brand ? seems definitely psu stuff.

also check if fgx card is seated in it's slot properly, secured tightly with screws.

Alok said:
Update : system started to boot but putting any load like game...hd movie or any software it goes black and restart automatically. . What this means ?? PSU or something different ?

Confirming that cpu temp are normal.

Try reassembling the system. Also, how old is the thermal paste?

harshilsharma63 said:
Try reassembling the system. Also, how old is the thermal paste?

he has already applied a new one....
@op, try another psu or try to boot without gpu.

In safe mode it stays and don't restart. ..I did prime 95 blend test ...it was fine. When I start in normal mode it restart without warning if I run any slight intensive process even a Google search in chrome. What now ?

harshilsharma63 said:
Try reassembling the system. Also, how old is the thermal paste?

Already done

icebags said:
how old is psu and what brand ? seems definitely psu stuff.

also check if fgx card is seated in it's slot properly, secured tightly with screws.

Corsair gs600 already mentioned. 18 months old only. Checked and properly seated/connected everything.

Conform that your system is not infected by scanning it in safe mode.

Ok will do. Also a fact making trouble that how everything run smooth on inverter supply.

friends, I want to confirm what is broken before calling for RMA on anything.

try ubuntu live cd

rijinpk1 said:
try ubuntu live cd

Nice idea ..going to take from a fellow.

It booted this time . I grabbed pic of hw monitor ... look here if anything wrong. ..
View attachment 13399
Now run prime95 test. Cpu temp is increasing ...normal - 37c ...test1 50c test2 ..60c....test 3...70c

the 12v line is dying. rma-ing psu is the next step. just to make sure, try hwinfo to see the same info or not.

also using your pc with that psu is not recommended. either lend another psu until you get replacement or do not use it.

also using your pc with that psu is not recommended. either lend another psu until you get replacement or do not use it.

UPDATE: here is what overall conditions 》
My pc has changed booting behavior. ..here is how it goes
1. Press power button
2. Wait till 1 long 2 short beep.
3. Hold power button to power off then turn on again.
4. It will start now with normal post beep. As far now it was found stable only one time ...but often its not stable you do any stressful process and screen goes black and pc reboots.

rijinpk1 said:
the 12v line is dying. rma-ing psu is the next step. just to make sure, try hwinfo to see the same info or not.

also using your pc with that psu is not recommended. either lend another psu until you get replacement or do not use it.

also using your pc with that psu is not recommended. either lend another psu until you get replacement or do not use it.

Oh I see. Thanks a lot. So finally its psu... that 12v line ..I will do RMA request now.
Btw how you identified. .

Oh I got it... it should be 11 point something but its not ..

hw monitor was not always correct in my case. so try hwinfo also.

Which part is powered by +12v btw..just curious
Don't laugh if ques goes to something foolish coz I don't know psu that well

Ok run hwinfo .... now its loads of stuff can't see voltage in this window btw
Got it

View attachment 13400
Here is what hwinfo says

it seems hw monitor was wrong. anyway try ubuntu.

Ok will boot by usb soon

did u run both when supplied from mains ? run hwinfo & monitor side by side.....

Not side by side but one by one.
Going to try ubuntu.

Ubuntu ran well.
I made clean install of Windows 7...now pc restart as I run a game.. (tried bioshock infinite , gta sa)