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#1 30-10-2009 01:25:16
- Silkie341
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PC not powering on
My brains are a bit scrambled so I need to be reminded what commonly causes the following:
I hit the power switch and the power light flashes once then it stays off. The PSU is getting power to the board so I'm thinking CPU but like I said I'm not thinking straight just now.
The machine was fine until I had to power off and there's been no storm in the area. Little help[?
Give me coffee and no one needs to get hurt! Well not physically anyway! "Nothing in this world worth having comes easy" Bob Kelso
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#2 30-10-2009 07:50:48
Re: PC not powering on
With a dead CPU the machine normally powers up but you get no beeps and a blank display.
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#4 30-10-2009 11:49:02
- Silkie341
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Re: PC not powering on
Ah yes there's a chance it may have come unseated when I moved it. Worth a try.
Give me coffee and no one needs to get hurt! Well not physically anyway! "Nothing in this world worth having comes easy" Bob Kelso
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#5 30-10-2009 13:07:25
- Silkie341
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Re: PC not powering on
No dice. I should know this as it seems very familiar. The single attempt to power on that fails and then it's stuck unless you remove the power lead from the mains first.
I'm fairly certain something odd happened on the last shutdown but of course I wasn't actually watching which is always the way. Sometimes computers seem to take on a nasty wilful personality all of their own especially as it was due to be replaced by a newer PC but waiting until I was at least half done would be too much to ask. 
Give me coffee and no one needs to get hurt! Well not physically anyway! "Nothing in this world worth having comes easy" Bob Kelso
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#6 30-10-2009 16:16:18
Re: PC not powering on
Remove all non essentials and then see if it powers on 
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#7 30-10-2009 19:07:31
- Silkie341
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Re: PC not powering on
I'm down to that but I feel terrible right now so I'd better leave it until the morning and a clear head.
Of course it's sods law that this is my current 'server' and I haven't got the replacement up and running yet.
Give me coffee and no one needs to get hurt! Well not physically anyway! "Nothing in this world worth having comes easy" Bob Kelso
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#8 05-11-2009 08:57:14
- Silkie341
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Re: PC not powering on
It's looking very grim. I eliminated everything but the Mainboard and the PSU and today I need to hook up a regular PSU outside the case to check that but either way shuttle spares of this age are down to hunting on Ebay. Damned if the thing didn't pick the nastiest point to break as in a week it's replacement would have been done although at least I should be able to get the data off the RAID as I have other Silicon Image chipset controllers.
What I was wondering was if the fan in the PSU had failed would this cause the abortive startup? The powers getting through as the CPU fan spins for a second but I'm not sure the PSU one does.
Give me coffee and no one needs to get hurt! Well not physically anyway! "Nothing in this world worth having comes easy" Bob Kelso
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#9 05-11-2009 09:37:53
- Jellyroll
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Re: PC not powering on
Have you pulled the mobo from the case and tried it "naked"? It could be shorting against the case somehow. That would produce the symptoms you're seeing, where the PSU starts momentarily, the fans spins briefly, then it stops again.
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#10 05-11-2009 10:27:49
- Silkie341
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Re: PC not powering on
Not fun on a Shuttle but after I try the PSU it's all I have left.
Give me coffee and no one needs to get hurt! Well not physically anyway! "Nothing in this world worth having comes easy" Bob Kelso
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#11 14-11-2009 11:44:35
- jerryh
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Re: PC not powering on
Have you sorted this yet?
I concur with JR (would I dare disagree !! )The symptons are the power supply overloading
I had exactly the same problem a few weeks ago, in my case it was caused by the power supply caused by a hard drive failure which was overloading the 12v rail
The fan starting and stopping indicates the 12 rail
Recommend you test the power supply I'm sure you know how to do it but anyway:
connect a fan (or any 12 device) to the normal 4 pin connector & disconnect everything else including the mobo.
Plug in to mains then:
On the 20 pin connector there is only one green wire (pin14) short this with a paperclip to zero volts - either one of the black wires next to it.
This will turn on the power supply if its ok.
A case fan should run with nothing else connected so is a good indicator of a 12v rail
So try the mobo bare, no graphics card, memory, and preferably no CPU
If fan runs add components one at a time to identify faulty one
If this is a case of suck eggs and granny then I apologise in advance
J
Oh No not again!!
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#12 14-11-2009 15:28:50
- Silkie341
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Re: PC not powering on
I've been sort of buried in problems lately and so I haven't had a chance yet but I appreciate the suggestions as they help me focus.
Give me coffee and no one needs to get hurt! Well not physically anyway! "Nothing in this world worth having comes easy" Bob Kelso
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