The following site has some diagnostic flowcharts for troubleshooting.
You might try them and see if they help find the problem(s). 
Bob Lendrim

http://www.fonerbooks.com/pcrepair.htm


>From: jimi moore <[log in to unmask]>
>Subject: Re: [PCBUILD] New Build
>
>Thanks Dean for your insightful reply. In fact we got a PS tester and the ps 
>was bad! We bought another one..checked it before installing it and it was 
>fine...low and behold. The same results for the system..can't get by post! 
>This was a bundle from tigerdirect which i've never had a problem with 
>before but i'm starting to wonder now.  jim
>
 
>From: "Dean Kukral" <[log in to unmask]>
>Subject: Re: [PCBUILD] New Build
>
>
>> It sort of points to the power supply, doesn't it?  You  had the same 
>> problem with the old system, and the other two parts test okay
>> in another system, so it is reasonable to suspect the power supply.
>>
>> Also, your two basic "known's" are not correct.  First of all, some things 
>> could be going and/or lit up, but the power supply still
>> could be weak enough to not be able to boot the whole system.  Second, 
>> things could have come dead on arrival.  Many of the bad
>> reviews on NewEgg.com come from people who got bad products.  Some even 
>> returned the product and got another bad product
>> replacement!  I think that you are right to think that this is rare.  But 
>> I can tell you that I once got an ASUS motherboard, which
>> in the past was known for quality, with bad networking hardware right out 
>> of the box.
>>
>> One thing that you might try is to unhook the power to the hard drive and 
>> see if you can get past POST.  That would indicate that
>> the power supply can supply a little power, but not enough to get the job 
>> done.  The one problem with this test is that some power
>> supplies need a load to start up, and the motherboard may not be enough of 
>> a load by itself.
>>
>> http://www.pcpower.com/support/ATX_troubleshoot.htm has a check for a 
>> power supply, but it is a very poor test.  Your power supply
>> could be failing and still pass this test.  (I have had a power supply 
>> that passed this test but was no good.) You might try it
>> anyway.  If it passes, then that does not mean anything, but if it fails, 
>> then you know that the power supply is bad.
>>
>> Make sure that the motherboard is standing well off of the case so that 
>> there is no chance of the traces on the bottom of the
>> motherboard touching the case, except where the stand-offs are screwed in.
>>
>> If you can borrow a power supply to try the system out, then that would be 
>> ideal.  Swapping in new parts one at a time can get
>> expensive.  Cheap power supplies are not too bad (nice to have a spare), 
>> but powerful game power supplies can run pretty expensive.
>>
>> And, of course, there is the time-honored technique of disconnecting 
>> everything and adding components one at a time, with the caveat
>> that the power supply may need a load to run at all.  So, you may have to 
>> leave a drive connected.  HTH  Dean Kukral
>>
>>
>> From: "jimi moore" <[log in to unmask]>
>> Subject: [PCBUILD] New Build
>>
>>
>> I've recently started building a new computer. I believe I've assembled 
>> all of the parts and connections correctly. The problem however is that upon
>> booting up, the system doesn't past POST. There are no sounds, and no beep.
>> There is also no red light showing at all. However all of the fans are
>> spinning, and there is a green light on the motherboard, so I know it's
>> getting power. My system specs are as follows:
>>
>> Power Supply: 700W GameXstream
>> Motherboard: Asus P5N-D
>> Processor: Intel Core 2 Quad Q6700
>> RAM: Two 2048MB sticks of DDR2 Corsair RAM.
>> Graphics Card: Nvidia 8800 GTS
>> HDD: 500 GB Western Digital Caviar
>>
>> The HDD, Graphics Card, and Power Supply are from my old system. Now, the
>> reason for building a new one in the first place was that my old one was
>> having the exact same error. I know the HDD works, because I've tested it 
>> in another machine. I've also tested the Graphics Card in another machine. 
>> Both worked flawlessly. I highly doubt it's the Power Supply, because of the
>> green light on the motherboard and the fact that all of the fans spin. I
>> also doubt the new parts I've ordered were shipped dead on arrival. Hence 
>> we have a problem that really confuses me. I am getting the same error in my
>> new machine as I was having in my old, but the only things that could be 
>> the problem I'm certain are not.
>> So, can anybody help me out here?   Jimi Moore
>>
>>
>>
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