Comp not booting anymore

[Krow]

Config:
AMD Phenom II X4 940
Gigabyte GA-MA790GP-UD4H
2x2GB Kingston DDR2 800MHz
2x2GB OCZ DDR2 800MHz
Corsair VX450W
1TB Seagate 7200.12
500GB Seagate 7200.12
CM Elite 330
TRUE 120 Rev C
2xDelta 120mm
Creative 2.1 Speakers
Samsung SyncMaster 793s 17" CRT

I was away from home for 5 months. In this time, my desktop was rarely used. First it refused to boot. I found that the problem was my 4 year old Hitachi 160GB HDD was dead. It had all my OS installations. My backup 500GB Seagate is fine.

Then I bought a new 1TB Seagate 7200.12 and installed Windows 7 Ultimate x64. The PC ran fine a couple of times. Now the problem is that when I boot the computer, it boots and as soon as it reaches the desktop, it powers off. This has become worse every time I tried to boot it.

Also, when it did boot, the audio refused to work, neither front panel or back panel connectors worked. My speakers and headphones are just fine (both work well on iPod) and I installed all drivers correctly. Previously everything was fine.

Now it refuses to even show POST. The blue light on my cabinet comes on when I press the power on button and it powers off within 5 seconds. Sometimes it boots, but it powers off instantly.

I removed all components and reassembled my rig after thorough dust cleaning.

I thought my power supply may have conked off or it might be the new HDD. So, I got my friend's Tagan TG500W-U37 and plugged it in. Same problem. I tried booting with his 1TB WD Caviar Green with his power supply. Same problem. These are working fine in his computer.


I am going to give him my Corsair VX450W and Seagate 1TB to test in his rig. Let's see what happens.

Is my mobo dead? Is it the RAM? Is it the processor? I am running out of ideas.

[asingh]

^^
Try with one RAM stick at a time.

[jerrin_ss5]

might be the RAM is at fault try what asingh said !!!