# PC starts up and restarts after 1 second



## tatsumaru (Apr 1, 2005)

Hi,

I've had this PC for the best part of 2 years now and it's not really given me any problems along the way. 

When I turn on the PC it will load for a second and then restart and do the same thing in an infinite loop (without any bleeps). I tried removing everything apart from the PSU MoBo and CPU and I can get it to start for around 10 seconds, this time it bleeps along the way and restarts - but the subsequent restarts after the initial ten second one only last for about a second, this time with a beep on each.

I've tried new thermal paste and even a new heatsink & fan for my CPU. I've also tried moving the RAM to other slots and removing the CMOS battery for well over an hour. 

I'm afraid I have no spares to check the PSU or Mobo so any action I do take in terms of replacing something is a risk, unless someone here has a good suggestion or is confident they know what it could be. I'm set to purchase a new MoBo and PSU but I'm not happy to part with the cash on something I may not need!

My setup is:
Nvidia 7900GS 256MB 
ASUS P5KC AiLifestyle Series iP35
Intel Core 2 Duo E8200
4x1GB OCZ DDR2 800MHz/PC2-6400 
Samsung SpinPoint HD501LJ 500GB SATAII 

This is all running on an Antec SL400P 400W PSU

My gut instinct is that the MoBo is faulty, but the signs tell me it must be the PSU. 

Thanks,

Karl


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## tatsumaru (Apr 1, 2005)

Correction:

When all hardware is removed - the time that the pc remains on for is random, it lasts for between 1 and 10 seconds. The bleeps sound as one long two short which after reading up would most likely be saying a video problem? (not that I think it has anything to do with the video card)


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## tatsumaru (Apr 1, 2005)

I tried a couple of tests on the PSU, both of which gave me the impression the PSU is fine - one of those tests included taking out the CPU and turning on the PC without it. The result was the PC stayed on indefinitely.

When I initially removed the CPU fan and heatsink I found that the heatsink (or at the very least the thermal compound) was not touching the CPU on one of the corners (this may have been because of a dodgy heatsink brace) I replaced the heatsink and applied some new thermal compound, but still the same prob. So now I'm wondering if the CPU could be the culprit. 

I also left the CMOS battery out for the whole night and I'm now no longer getting any system bleeps.

Anyone got any ideas?


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## hhnq04 (Mar 19, 2008)

400W is a little light for a PCI-E card. It may have ran for the two years, but over time your components wear down (PSU included) and it may not be able to output the required power for your system anymore. I would consider looking into Corsair 650TX. I would be comfortable with a 550W, but this one is cheaper than their 550W and gives you headroom if / when you upgrade other components.


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## Tyree (May 10, 2009)

Same thoughts as hhnq04. Another good PSU choice to meet your requirements and save a few dollars without sacrificing quality.
SeaSonic 620W about $80: http://www.newegg.com/Product/Product.aspx?Item=N82E16817151096


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## tatsumaru (Apr 1, 2005)

Hi again,

I will be looking to get a new PSU at some point, especially if I need to get a new mobo/cpu - but I'm almost certain that the PSU is not at fault here. 

I have tried the PSU with only the motherboard and CPU but it still does the same thing, but when I try with everything except the CPU (Mobo, GFX card, HDD, DVD-RW, 5 system fans & 4x1GB RAM) it stays on no problem (other than it can't boot without a CPU of course)

Using http://extreme.outervision.com/PSUEngine it tells me that my recommended PSU wattage is 263 (which is partly why I bought this PSU in the first place) and I know this is not necessarily gonna give me a 100% accurate recommendation, but 263 is quite a bit lower than 400.

Is there anything I could do within my limits to check the CPU or motherboard in some way? 

Also thanks on your PSU recommendations - Is there a motherboard and CPU combination you could recommend? A motherboard which supports 4xDDR2 ram modules and a CPU which is at least as fast as the E8200 I currently have?

Thanks for your time

Karl


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## Tyree (May 10, 2009)

This forum recommends 550W minimum for any system using a PCI-E GPU.
My money is still on the Antec PSU being the problem.


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## tatsumaru (Apr 1, 2005)

Hi again,

I must thank you for the advice! The new PSU (I actually went with the Corsair 650tx one) worked and my PC is up and running once more  Thanks!

I have to ask though - what was it that made you suspect it was the PSU? Was it just the wattage of my old PSU?

Thanks again

Karl


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## hhnq04 (Mar 19, 2008)

Glad to hear it's back in working order. We recommend a minimum 550W for a system using a PCI-E video card, so seeing that you were using 400W was the first hint that it could very well be a power problem. System components, PSU included, wear and decline over time. We suggest a 550W+ PSU to help give some headroom so that the system can still operate safely even as the unit slowly gets less efficient.


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## Tyree (May 10, 2009)

tatsumaru said:


> I have to ask though - what was it that made you suspect it was the PSU? Was it just the wattage of my old PSU?
> 
> 
> 
> Karl


Your problem sounded like a power issue, your PSU was underpowered and Antec PSU's aren't the good quality they use to be.
Glad to hear your problem is resolved.


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## speedster123 (Oct 18, 2006)

Its lucky you didnt suffer system damage.


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