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The computer in question worked last week. It's brand new, never been connected to the internet, up-to-date parts, etc.

Last week, I installed some 3D software on it, then shut it down and waited for the license files that arrived this week. I've done this to 4 other PCs with the same hardware and software.

I've tried:

  • Hooking it up to 3 different monitors
  • using different video cables
  • 2 other graphics cards

and a handful of other things like switching which port it's plugged into before and after a restart. I have the driver disc, and a windows reinstallation disc, but they won't do me any good because no display at all for any interval of time.

All the fans are moving: psu, gfx, cpu etc, so I don't believe it's a power issue. Here are the specs I know of:

  • 4GB RAM
  • 8800 GTX
  • 700w PSU
  • Intel dual core (not sure of model)

Anyways, I'm open to ideas.

EDIT:: Another thing I wanted to mention is when I plug in a keyboard, it's not detecting it at all. This keyboard works on other PCs, but it's not getting any power from this one (no caps, num, scroll lock lights working)

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Can you see enough when it first boots to get into the BIOS? –  Jed Daniels Jun 18 '10 at 14:57
    
Nope, no display at all. The monitor detects it is plugged in, but no signal is coming through so the monitor goes directly into standby. –  Justen Jun 18 '10 at 15:03

3 Answers 3

up vote 4 down vote accepted

I tend to agree with BloodPhilia's post, it sounds like the motherboard or some other basic hardware failure.

The only way I know how to approach situations like this is to isolate the problem by trial and error. It's tedious, but it's all I can recommend.

Start by stripping the computer down to bare essentials. Completely disconnect all the hard drives, both data and power.

Remove all USB devices except those absolutely needed to boot. (I'd frankly try booting at least once with no mouse and keyboard just to see if anything shows up on the monitor).

Pull out all adapter cards and all but 1 known good memory DIMM. If there is no integrated video on the motherboard then install a known good video card and connect it to a known good monitor. (At times like these I'm glad I still have some ancient PCI video cards I can use as an alternative).

Power up the computer and see if you can get into the BIOS. If you can't then I would suspect either a motherboard (my bet) or PSU problem.

If you can reach the BIOS with parts removed, then start restoring the components to see where it starts to fail again.

If you verify that all the parts are good by testing them in other systems and this system still doesn't work then I don't know what else it could be but the motherboard.

(Well, it could possible be a bad connection. Reseating the adapter cards, RAM, and power connectors usually fixes that though. Sounds like you have covered that already though.)

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+1 for improving my answer =) –  BloodPhilia Jun 18 '10 at 15:24
    
Thanks for the response. I'll try stripping it out if I get time. The last thing I tried was taking out the CMOS battery incase some cosmic ray or something messed with a vital setting. No such luck :) –  Justen Jun 18 '10 at 15:31
1  
The only thing that really made sense (to me) for my configuration was taking out the RAM. So I took out all the sticks, examined em for any burn marks or other indications of something detrimental, then stuck one in and it booted up. Thanks for the help. –  Justen Jun 18 '10 at 15:51

Sounds like your motherboard's failing since it's not detecting any keyboards as well.

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I'd be tending to agree with BloodPhilia and irrational John however it's probably worth testing another PSU to make sure it's not that before you send the motherboard back.

I've previously had experiences where the PSU fan would spin up fine, and even reported correct voltages on a PSU tester, however soon as it was put under load it would die and simply leave a single light on the motherboard flashing weakly.

So to sum up all the posts so far:

  1. Try to remove unnecessary external devices and see if it posts.

  2. Try to remove all other hardware and try without RAM then again with just one known working stick (it may be that a stick has come unseated or that perhaps there's something in one of the sockets causing a bad connection so even try it in different slots)

  3. Other than that without any other tools your best bet then is to take all the information and tests you've tried so far back to whomever supplied it and arrange replacement.

Best of luck with it all!

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