Urgent help with my new PC!

[-73H_64M3R-]

When I turn the PC on, it runs for a while then turns off, then the screen goes blank. When it turns off, there is an orange blinking light on the motherboard as opposed to green one. Any experienced builders here know what's happening? This is my first time DIY-ing a PC.

[SoulsCollective]

Without more details it's going to be almost impossible to help you.

To start with we're at least going to need to know what components you used, and also some details as to how you've set the machine up (ie. is it in a case? Stock cooling? Aftermarket air? Water cooled?), what OS you have installed or if it shuts down before you get a chance to install anything, how far through POST you get or any beep error codes from the mobo, etc etc, but from what you've said so far my first guess would be that you've not seated the CPU cooler properly and you're triggering thermal shutdown from the CPU overheating.

[-73H_64M3R-]

Without more details it's going to be almost impossible to help you.

To start with we're at least going to need to know what components you used, and also some details as to how you've set the machine up (ie. is it in a case? Stock cooling? Aftermarket air? Water cooled?), what OS you have installed or if it shuts down before you get a chance to install anything, how far through POST you get or any beep error codes from the mobo, etc etc, but from what you've said so far my first guess would be that you've not seated the CPU cooler properly and you're triggering thermal shutdown from the CPU overheating.

Sorry for not providing any more information. I managed to get into the BIOS before it shut down again and it reported a temperature of 85 degrees C on the processor. However, I've reseated the cooler but it won't turn on now.

Intel Core i7 920
MSI X58 PRO-E
MSI R4890
Team Xtreem DDR3 1600 MHz Dual Channel
OCZ MODXSTREAM 780 W

All stock cooling. No beeping sounds from the motherboard, not even when I turn it on. It's all silent. I didn't get a chance to install anything at all. Once, I even got an error for "overclocking error".

[RacingTurtle]

Obviously 85c is too high and the pc is shutting down for safety - you need to to ensure that you have applied TIM correctly and seated the cooler properly - make sure the pushpins are fully clipped in.
Now that it wont turn on at all it sounds as though its shorting - are any fans coming on? Any lights on the motherboard?

[-73H_64M3R-]

Obviously 85c is too high and the pc is shutting down for safety - you need to to ensure that you have applied TIM correctly and seated the cooler properly - make sure the pushpins are fully clipped in.
Now that it wont turn on at all it sounds as though its shorting - are any fans coming on? Any lights on the motherboard?

Only that orange light on the motherboard. Even if I didn't turn on the power from the mains, if I flick the power switch on the power supply to on, it will have orange light. No fans turned on.

[SoulsCollective]

As above, it sounds like your problem is overheating, compounded by perhaps a shorting issue.

Try removing everything from the case, resting the motherboard on top of some non-conductive surface like a cardboard box (most folks use the box their mobo came in for this), and starting with only the CPU, one stick of RAM, and the graphics card plugged in (you'll need to make sure that the GPU expansion bracket is positioned so it can overhang the edge of the motherboard and whatever you're resting the board on, otherwise it'll not sit flat and push itself halfway out of the socket). Be firm with the pushpins on the cooler, they're hard to get in, and try putting one hand underneath the motherboard as you push - each side should make a distinct 'click' if it's properly seated. If you can get into BIOS and stay there with reasonable temperatures (somewhere around 50 degrees C) without restarting, try shutting down and adding components (ie. more RAM, HDD, DVD drive, any other expansion cards) one by one to see if your system will still boot and stay powered on with each new addition.

If you can build your entire system outside of your case and it'll stay on, disassemble and try reassembly inside your case (as above, which case are you using?). If your system now does not boot, you're seeing a shorting issue caused by something in the case, and we can try and narrow it down some.

[-73H_64M3R-]

As above, it sounds like your problem is overheating, compounded by perhaps a shorting issue.

Try removing everything from the case, resting the motherboard on top of some non-conductive surface like a cardboard box (most folks use the box their mobo came in for this), and starting with only the CPU, one stick of RAM, and the graphics card plugged in (you'll need to make sure that the GPU expansion bracket is positioned so it can overhang the edge of the motherboard and whatever you're resting the board on, otherwise it'll not sit flat and push itself halfway out of the socket). Be firm with the pushpins on the cooler, they're hard to get in, and try putting one hand underneath the motherboard as you push - each side should make a distinct 'click' if it's properly seated. If you can get into BIOS and stay there with reasonable temperatures (somewhere around 50 degrees C) without restarting, try shutting down and adding components (ie. more RAM, HDD, DVD drive, any other expansion cards) one by one to see if your system will still boot and stay powered on with each new addition.

If you can build your entire system outside of your case and it'll stay on, disassemble and try reassembly inside your case (as above, which case are you using?). If your system now does not boot, you're seeing a shorting issue caused by something in the case, and we can try and narrow it down some.

Thanks. Good idea! I'll try it. Troublesome but no choice. I hope I didn't kill any components. Actually I did push the pins down with a click.

[-73H_64M3R-]

It finally works after I ran it naked! I have narrowed down the possibilities. It's either I did something wrong inside the case (short circuit/bad connection of the wires because I bent them a lot) or I overload the socket in my room (when it worked, I was running from the mains). It has ran for 5 minutes without any fail.

[SoulsCollective]

Before you build the system in the case again, look carefully at all the standoffs screwed into the case panel. Do any have rough edges? Are there any obvious tabs of metal sticking out somewhere that could be shorting? Anything on the motherboard?

I doubt you've done any permanent damage, but it's worth trying to reduce possibilities of harm before you try again.

[B-Shot]

Pull the MB out and fire it up on the table to eliminate grounding issues with the case and see if it will post again.

[SoulsCollective]

Pull the MB out and fire it up on the table to eliminate grounding issues with the case and see if it will post again.

Lol. Already been recommended, already been done, results already been posted.

Try removing everything from the case, resting the motherboard on top of some non-conductive surface like a cardboard box (most folks use the box their mobo came in for this), and starting with only the CPU, one stick of RAM, and the graphics card plugged in (you'll need to make sure that the GPU expansion bracket is positioned so it can overhang the edge of the motherboard and whatever you're resting the board on, otherwise it'll not sit flat and push itself halfway out of the socket).
...
If your system now does not boot, you're seeing a shorting issue caused by something in the case, and we can try and narrow it down some.

It finally works after I ran it naked! I have narrowed down the possibilities. It's either I did something wrong inside the case (short circuit/bad connection of the wires because I bent them a lot) or I overload the socket in my room (when it worked, I was running from the mains). It has ran for 5 minutes without any fail.

[RacingTurtle]

Glad you seem to have it sorted. Its such a simple thing but it catches out people a hell of alot. My first PC build had this issue, took me 2/3 days of googling to figure out what the problem was!