No video signal (with an interesting twist..)

February 15, 2011 at 12:34:13
Specs: Windows XP, Athlon XP 3500+ / 1 GB RAM
Hello all,

OK I know this is a thousand year old question but this is unique in the way it pops out..
So here it goes,

My specs first,
1) Epox 9NPA Ultra+ Mobo
2) Athlon XP 3500+ CPU
3) 1 GB RAM
4) 8800 GTS video card
5) 400 W Silverpower PSU

First time I had the no-signal problem was, after a power outage while watching a movie. Power went off and then I waited for it to come back (There was a spike in the power while I was waiting for the it to come back on btw and power went off instantly again, just to note), when the power came back on I powered on the PC and continued with no probs.( Tomorrow morning, when I turned on the PC the monitor would get no signal at all no matter what I did. But the PC booted and the hard disk loaded the OS. Just no signal from the video card at all.. So I tried everything including;

1) Removing power cable and pressing on button for 30 secs
2) Resetting the BIOS and removing the CMOS battery
3) Removing/moving the RAMs
4) Pulling all the connections out 1 by 1 and try powering on
5) Trying other PSUs to see if the PSU was faulty

But nothing worked so I took it to a service and they told me that my video card (6600 GT back then) was *kind of* faulty meaning it would not work on my PC but it would work on other PCs (?!?) and told me that while it worked on other PCs, it wouldnt mean that it was functional and that it may do the same in other PCs sometime later and advised me to get a new card (because they had tested another PCI-e card on my PC and display was on meaning there was no problems with the PCI-e slot either - I guess-) So I did get a second hand 8800 GTS, plugged it in and voila! It worked without any problems at all.

Then I used the computer for about 2 months UNTIL yesterday where it started to do the same problem out of nowhere (no power outages, no nothing..) No video signal to the computer at all.. I had the old card (6660 GT) lying around so I plugged it in to try it out. It didn't work naturally but the monitor light would turn green for 1-2 seconds before well.. Displaying nothing at all lol.. Then the light would turn yellow. After the second try, it doesnt even do that.

So yeah... This is the problem.. 2 cards and no video signal at all. I dont know how this might help but a couple of thing I noticed this time

1) The PC boots while there is no signal, but I have to press enter at some point for it to continue loading from the Hard drive. Since theres no signal I cant see if theres any message of course.
2) When the PC is booting first the USB mouse and keyboard powers on but after a while their lights goes off and doesnt come back. I dont remember getting this problem first time with the older case.
3) Epox mobo has an on-board diagnostic LED which shows FF (fully functional) after the boot and also it has 3 blue LEDs near RAM slots, CPU and another part I cant remember right now. But they all do light up indicating that there's no problem with those parts either.

While I havent had the chance to try the 8800 GTS with another computer to see if it worked, Im guessing it might since this was the case the first time this problem occured.

This time I cant suspect anything. I mean I am left w/o any thoughts as to what might be wrong, I've tried everything to no avail... It may be the video card, the PCI-e slot, the ram etc etc... I mean what are the odds of this problem happening the second time (I haven't even touched the computer after I plugged the new video card) I cant still pinpoint the problem and I dont have the funds to replace any components anymore. So I'm practically helpless at this point and need my PC for my work.. I would greatly appreciate any comments about this problem. Thank you..

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February 15, 2011 at 13:29:21
Any beeps at startup? If not, remove all the RAM, then try to boot. If the system is working properly, it should beep like mad. If it doesn't, the problem is either with the CPU, board or power supply.

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February 15, 2011 at 14:30:49
Thank you for your reply mickliq

Unfortunately, my motherboard doesnt have a on-board motherboard speaker.. I guess the next step is to get one and see what beeps it gives. I will post the beep codes it gives out here. Do you think the POST beeps will help me pinpoint the problem or just give me a sign that there is something wrong with the components?

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February 15, 2011 at 16:48:13
I have stumbled upon another advice which may be the cause of all this: PSU - I'd be grateful if you could comment on that;

Turns out that my PSU does not meet the minimum requirements for my card (8600 GTS)
Silverpower SP-400p1b has 18A Amperage output on the +12 volts rail while 8600 GTS requires between 22-30A (changes from source to source so Im not exactly sure of the value but it is definitely above my PSU's specs) on the +12 volts rail. However considering that I have been using this card for about 2 months, do you think that this shortage may be the cause of this fail?

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Related Solutions

February 15, 2011 at 17:10:21
A power failure event that produces power spikes or power surges can damage anything on the mboard or anything connected to it.It frequently damages the power supply.

By the way, I have two old computers with Epox SS7 mboards that still work fine, and one of the last ones they made - AD580 XR - that had the PCI-E X16 slot circuits damaged by a power failure event.

Yes, the inadequate power supply is probably the cause of your present problem. If it's the same one that was exposed to the power failure event it could have been damaged by that too.

Even if the PS was not damaged by the power failure event, when it does not have enough capacity for the video chipset on a card you're using, it often works okay anyway at first but it is damaged from it being constantly overloaded and will eventually cause you problems or even fail completely.

Try another known good power supply from a working system that has enough capacity if you can before buying one.

Your power supply must have at least the minimum capacity required to support a system with the graphics card you are using installed, or the max graphics card you might install in the future.
(Onboard video - video built into the mboard - IS NOT A CARD ! )
If that info is not in the ad for the video card, you can go to the video card maker's web site and look up the specs for the model - often under system requirements - the minimum PS wattage, and, more important, the minimum amperage the PS must supply at 12v is stated. If you don't find that, any card with the same video chipset including any letters after the model number has very similar minimum PS requirements. Some power supplies have two or more +12v ratings - in that case, add those ratings to determine the total +12v current capacity.

If you're a gamer...
In most if not all cases, the max capacity rating of the PS is an intermittent rating. It's recommended that you do not load your PS to any more that 80% of that rating if you are going to be using something that puts a constant load on it, such as playing a recent game for hours on end. In that case, you multiply the min capacity stated for the system with the particular video chipset on the card by 1.25 to find the min. capacity of the PS you should get.

If you need to get a PS with more capacity, you can usually replace it with any decent quality standard sized standard ATX PS.

Standard (PS/2) power supply size - 86mm high, 150mm wide, 140mm deep, or 3 3/8" h x 5 7/8" w x 5 1/2" d , or very close to that, though the depth can be more or less for some PSs.

Don't buy an el-cheapo (in quality) PS.
See response 3 in this:

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February 16, 2011 at 03:45:28
Wow great detailed post thank you!

I have narrowed down the problem to the following
1) Bad PSU
2) Bad caps on the MB
3) Failed PCI-e port on the MB

I have a question about this tubesandwires; you said that your MB AD580 XR had its PCI-e slot damaged by power failure. Is there a way to understand this for sure? Because I think it is either this or the PSU..

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February 16, 2011 at 08:36:16
First - try connecting another used known good PS that has enough capacity if you can.

If you DO see evidence of bad caps...
Epox was a lot less likely to have that problem on their mboards than many other mboard makers, but they did have that problem with some models.

In most cases it's not worth the time and trouble it takes to fix the problem - most people and techs just get another mboard, used or new, that is NOT the same model that is at least compatible with the cpu, if not both the cpu and the ram, you already have.

If you replace the bad caps BEFORE the mboard will not boot because of the bad caps, you have the best chance of restoring the mboard to working fine again.
You would be wasting your time replacing them unless you replace ALL the capacitors that have the same brand marking on them, because ANY of the ones that have not already failed made by that brand are likely to fail in the future.

If you DO want to fix the bad caps on your present mboard.......
If you need a source of the proper capacitors to replace them yourself, or if you live in North America and would rather have a professional do that for you, checkout this web site:

This was the original bad capacitor problem - has some example pictures.
History of why the exploding capacitors and which mboard makers were affected:

What to look for, mboard symptoms, example pictures:
Home page that site
- what the problem is caused by
- he says there are STILL bad capacitors on more recent mboards.

Pictures of blown capacitors, other components, power supplies, Athlon cpu's, etc.:

- links on left to economical available premade or custom capacitor kits, and/or you can ship the mboard to him and he will replace the capacitors for a flat fee (including the capacitors) plus shipping (North America only).

" said that your MB AD580 XR had its PCI-e slot damaged by power failure. Is there a way to understand this for sure?"

There seems to be nothing else wrong with that mboard, and I did get video from a PCI-E X16 card but there were serious problems with the video after the power failure event (more than one of them actually) and that card eventually failed when I installed the card in a new mboard. When I tried a new video card in the PCI-E X16 slot I did have video but there were still serious video problems. A PCI video card works fine with that mboard.
I bought the mboard for a disabled girl's system and she required a TV card - the failed card and the new card were / are both PCI-E X16 ATI AIW cards, the new Visiontex HD AIW card cost a lot more than a new mboard, she had limited finds, so I had to get another mboard for her.
I would still be using that mboard if I had bought another CPU and ram for it.

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