CPU/Mobo PC not booting up - help

[tech.addict]

My PC has the following configuration:
AMD 4400 X2
MSI 690V Mobo
2 X 1GB RAM
ASUS 4670 GFX card
80GB + 500 GB HDD

The PC was working alright - but from yesterday night after I shutdown the PC and tried to restart after sometime - it is not starting at all. No display, no HDD activity light and no beep codes also.

I tried the following:

i) Removed the RAMs, cleaned, reseated them. Also tried using only one module to figure out any RAM problem. Also tried different RAM sockets.

ii) Booted the PC only with Proccy and RAM

iii) Removed CMOS battery and cleared CMOS setting

iv) Removed the graphics card and tried using onboard video

v) A different PSU

After fiddling with the PC sometime last night, the PC started working, it worked for 4 hours at a stretch without any problem. I shut down the PC at 2AM at night and went to sleep. This morning when I tried to start it up - the problem reappeared. I tried all the steps mentioned above again this morning but no effect.

What may be the problem here? As the PC is not even giving any error beep codes and there is no display - is the problem with the Mobo?

 

[hash]

Whats the PSU that you own? And did you try it with another PSU this morning or with your own PSU?

 

[tech.addict]

Already tried that.

 

[neojjjk]

check psu....and mobo

 

[The Sauron]

Some time faulty cabinet power button cause such behavior, try interchanging with reset button / direct powerup by shorting mainboard power pins. Try system outside cabby to ruleout any shorting issue.

What exactly happens during fail boot like on powering up cpu fan spins for a second then stop?

 

[kekerode]

looks like problem with mobo only ... had similar issue with my asus board in past and got it rmaed

upgrade ur bios ... it may solve issue ... also check ur ram in motherboard's compatibility list

 

[tech.addict]

Some time faulty cabinet power button cause such behavior, try interchanging with reset button / direct powerup by shorting mainboard power pins. Try system outside cabby to ruleout any shorting issue.
What exactly happens during fail boot like on powering up cpu fan spins for a second then stop?

All fans and indicators keep running until I switch off the PC. And also I have to keep the power switch for a long time to switch off the unit. Will dismantle the unit totally today and try.

looks like problem with mobo only ... had similar issue with my asus board in past and got it rmaed

upgrade ur bios ... it may solve issue ... also check ur ram in motherboard's compatibility list

How to upgrade BIOS - the system is not even showing POST?

If everything fails I will get the Mobo checked and try to get it RMAed.