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I have a Dell XPS 420 which i recently upgraded with a EVGA GTX 550TI and a 80GB SSD Drive. I converted this machine into a home theater PC. Which I've always had on.

The computer wasn't responding, and so i restarted it and when it started, video ports showing static. I was getting static on my TV thru both DVI ports and the mini HDMI port.

I assumed my video card had gone bad, but i completely replaced it and still the same behavior is occurring. I do not know how to diagnosis this issue. Any thoughts?

UDPATE - Answering Questions (thanks for suggesting)

  • I have multiple cables (a DVI->HDMI cable & several HDMI cables (with a Mini-HDMI->HDMI adapter).
  • I have tried multiple inputs (plugging the bad computer in HDMI Input 1, HDMI Input 2)
  • I have also tried plugging in my playstation into HDMI Input 1, HDMI Input 2, and it works in both slots.
  • All devices are plugged into the same power strip.
  • The static is pure static from top to bottom, it's not covering anything up. It's pretty clear, tho, as in you can see each and every pixel.
  • Also, the static starts up when i start the machine and the TV is plugged in. If I unplug it, and then re-plug it in, the static doesn't show.
  • I can take a picture of it after work and post it.

Due to this, i'm farily confident it's the computer only that has an issue.

Thanks again!

share|improve this question
is it showing static on top of what you should see, or only static? Also, have you tried the video card on another system? – Journeyman Geek Mar 26 '12 at 8:22

Thoughts, it is possible that the curcuit in the tv that processes the data , the "display engine" for the digital input data, has a flaw or temporary bug. Because a TV can be "always on" with standby curcuits, Test by Un-Plugging the TV , wait 20 seconds , and plug it back in. (aka full hardware reset of the tv)
I assume that you can use the TV with channels, or other video signals and it does not have a problem? So any problem it could have is between the digital data stream and the display engine?

Other things I can think of might be a power issue between devices, try a different plug , or plug into the same socket. That isnt likly because you had it all working before. Unless you moved things around , while making other changes.

Recheck your cables, usually with digital signals it is all or nothing, but there can be a tiny place where it isnt all :-)

What is they type of static? blocks , lines , grain, color? got a picture of it? Is it constant , intermittant or random?

Did you test by turning Off everything else in whole House :-) to see if any weird interfearing item might exist? The main switch box makes doing that easy.

If the power failed, which may have caused any original problems with the computer, what about some surge protectors (power strips) with MOVs, power switches that might not be switched fully or carbonised contacts? A few quick Sharp switches of them back and forth, while the devices are off to re-make electrical contact, to test. If power Failed in a house or a surge happend, there are Many thing I can think of that have cleanups, and capacitors, and protection and FCC kinds of things that can Fail, so it doesnt hurt to test with everything shut off at the mains.

There has to be many other things, but a Picture or description of the type of static might provide a few more clues.

It is possible that a video card has a specific fatal flaw, and that flaw shows up in a lot of them from the same manufacture. A quick search of problems with the specific card model name , to see what problems people have with it, could put that to rest.

The PSU power, if you have a voltmeter, a quick check of any of the loose 12V lines would be easy enough. Check for the 12Volt DC , (with the meter switched and connected proper) , then check with the meter on AC Volts on the same 12V lines, which can tell if the DC is dirty or of the PSU has a bad problem.

share|improve this answer
I added some answers the the question to my original post. thanks – Roy Rico Mar 26 '12 at 14:55
Test with a simple 3way extention cord. because some power strips have some minor curcuitry in them. Confirm it completly clears up when you re-initilise the tv with the video card already operating? Because that sounds more like the TV being pickey about what might not be a really good clean data stream from the video card, at first. For that testing the 12V power on the computer WHEN it does the turn-on, posting is a time when a lot of power is needed initially from the PSU. – Psycogeek Mar 26 '12 at 18:12
it was all working at one time, just fine, then stopped. I don't think it has to do with the TV, but i'll try it out. – Roy Rico Mar 26 '12 at 20:43
@RoyRico while it could have to do with the tv, I was thinking combination. The tv expecting a clean data stream from the video card, and not getting it, and not clearing up when it was finnaly a good signal. – Psycogeek Mar 27 '12 at 22:35

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