# Computer can't boot, shuts down before getting to bios/OS



## boswelj3 (Jan 7, 2009)

Hey there,

I am trying to revive a computer I built about a year ago. Soon after I built it, it started experiencing trouble booting up -- it would shut down a couple seconds after its first try, then restart itself and usually recover and boot successfully and run fine after that. 

A couple months ago, it started acting up even more, and would randomly shut down during gaming and other cpu-intensive activities. This made me think it was an overheating or PSU problem, based on my googling. So I bought a new, higher wattage power supply (700w). Since attempting a boot with the new power supply the computer is now failing to boot at all, and always shutting down or restarting before i can do anything in bios or get to the OS. I reinstalled my old PSU and the problem persists. 

I am a novice to this field so please offer me any advice you can give. My specs:

Motherboard: Abit IP35 'Off Limits'
CPU: Intel Q6600 Quad Core
Ram: 4 GB Corsair
GPU: NVidia Gforce 8800GTS
PSU: Corsair 520W
HDD: WD 750GB

Thanks!

-John


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## manic (Aug 2, 2005)

Run the board outside of the case. You may be grounding somewhere.
Theres a stickey thread in the hardware section of this forum, called
bench testing.


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## VazT (May 30, 2007)

Another thing to check is the Thermal Compound between the CPU and CPU fan. You say you built the computer a year ago...did you apply the thermal compound? or if you have removed the fan from the CPU at anytime between then and now you may need to reapply. This will cause the PC to over heat and act as you are describing.


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## boswelj3 (Jan 7, 2009)

I followed the tutorial on bench testing meticulously and I am still having the same problem. I can get occasionally get into bios for a number of seconds before it shuts down.

I do not recall applying thermal compound, unless it came with the processor and instructed me and i have since forgotten. Do they carry it in a typical computer shop? is that a common problem?

Thanks for your help.


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## kev..uk (May 17, 2008)

without the thermal Compound between the CPU and CPU fan this would cause a big heat problem.
in my novice opinion this will be the problem


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## grimx133 (Jan 15, 2008)

It is a very common problem. Any time a heatsink is taken off, even for a second, the old must be cleaned and new thermal paste applied.
http://www.arcticsilver.com/arctic_silver_instructions.htm 
Any shop that sells computer components should also carry thermal paste. However, it can be a bit difficult to find locally, I always order online. 

Here's the arctic silver instructions. http://www.arcticsilver.com/arctic_silver_instructions.htm
Arctic Silver 5 is a fine paste, as is Artic Cooling's MX-2. I have and use both.
To clean old paste, use the highest purity isopropyl alcohol (90%+) that you can get from a local pharmacy. Arctic Silver's ArctiClean also works very nicely, but alcohol works just as good and it easier to obtain. Don't use too much at once, a few drops at a time, wipe with a paper towel, and repeat until it is totally clean, both the top of the cpu and the bottom of the heatsink. Do not let any liquids overflow and get on the board.


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## dai (Jul 2, 2004)

did you remove the protective plastic from the cpu before installing


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## manic (Aug 2, 2005)

Try a different video card. If you havent messed with the heat sink
fan, or the cpu, I doubt that is the problem. When it shuts off are the
fans still running, and you have a blank screen, or does everything
shut down.


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## boswelj3 (Jan 7, 2009)

Thanks for your responses. I did remove the plastic covering on the cpu before installing. Also, while installing the other PSU to see if that was the problem, i removed the heat sink and cleared dust out of the fan, so the thermal paste might be the problem. All fans spin normally at startup and at shutdown they slowly die out while everything else comes to an abrupt halt. 

I will go looking for some paste at some local computer supply shops and report my findings.


John


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## boswelj3 (Jan 7, 2009)

Hey all,

Thanks a ton! After applying thermal paste to the heat spreader I am able to boot into windows. However, whenever i boot up the system after shutting down, everything starts up and shuts down after about 5 seconds, then resets itself and works smoothly. this is similar to what occured to the system a couple months after first building it. any ideas? it can't be the PSU (tried another one), maybe its the video card but i don't have another to replace it. Thanks for your advice.

John


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## dai (Jul 2, 2004)

check for a bios update


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## kev..uk (May 17, 2008)

Q: are u using the normal stock fan kit ?

IF not mate i would invest in high end heat sink kit because the Intel Q6600 Quad Core is well known to run very hot and would explane your symptom's 

http://www.pixmania.co.uk/uk/uk/688425/art/akasa/cpu-fan-multisocket-evo.html?srcid=867 just a idear


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