[Solved] Zero visual

[Pixelkitten]

Backstory:
After getting a temp-job last summer, I finally had the cash to upgrade my desktop. I decided that the old stuff could go to my mothers PC, since it was from 2003 and my dad wouldn't stop complaining about how slow it was. After battling my inherent laziness and a problem with PATA-devices which turned out to be endemic to all Asus P8H67 MBs, I got started on the upgrading.

First, it turned out that the chassis was too small for the MB. Go to store, buy new chassis, move all components into new chassis. Then I noticed that the old 300W PSU didn't have enough Molex connectors to power everything. Go to store, buy new PSU, install. After a frantic search for the drivers, I was ready to actually get it to boot. Or as it turned out, try to get it to boot.

Problem:
I'm simply not getting an image. I press the power button, fans hum, monitor says "PLEASE CHECK SIGNAL". At first I thought I had just plugged it into the wrong connector, the graphics cards has two DVI connectors, and even though I plugged it into the one marked "1" something was obviously wrong. No signal on the other one either. Huh.

And once again I find myself turning to you FPCH, because I can't figure out whats wrong with it. I have some hunches though; it might be the MB, since it'll soon be seven years old, and past it's prime (though I have no idea if it's capacitor plague or the CMOS battery). It might be the monitor, since that's the really ancient piece of hardware involved in this. It's been with us since April 2000 when my mom bought our first Pentium II. That's actually the most probable explanation now that I think of it.

It's a bit too late now to lug around monitors, even if they're LCDs. I'll try it tomorrow and tell you the results. In the mean time, I'd be grateful for any ideas, speculations and epiphanies you might have.

Here are the specs involved in this by the way:

Motherboard = ASRock 939Dual-SATA2

Processor = AMD Athlon 64 X2

Graphics card = Nvidia GeForce 7800 GTX

500W PSU

2 GB RAM

1 40GB PATA HDD (Documents)

1 500GB PATA HDD ("New and shiny")

CD Writer

Mouse, keyboard, speakers etc.

 

[KenB]

Hi,

The first thing you need to do is to check the monitor on another machine - or another working monitor on your machine.

If the monitor is OK - do you have on-board video to try?
If so - connect the monitor to this to try.

 

[Pixelkitten]

Hi,

The first thing you need to do is to check the monitor on another machine - or another working monitor on your machine.

If the monitor is OK - do you have on-board video to try?
If so - connect the monitor to this to try.

Hi Ken!
If I understood that correctly, that's exactly what I'll do tomorrow. I'll plug my LCD in, since I know it works with DVI. The old monitor seems to handle VGA, but I'm not so sure that it can handle DVI and I don't know if the computer is even sending any analog signals. Currently I'm using an adapter to bridge the computers DVI connectors and the monitors VGA connector.

 

[KenB]

Hi,

The old monitor seems to handle VGA, but I'm not so sure that it can handle DVI

The DVI outlet of your Video Card transmits both Digital and Analogue data.
The VGA monitor uses the Analogue signal.
There wouldn't be an adapter if it wasn't possible to "bridge" the two

Do you have a VGA on-board connection to try ?

 

[Pixelkitten]

Do you have a VGA on-board connection to try ?

No, the Geforce 7800 has two DVI and one S-Video connector.

I could change to a card with a VGA connector (I think I have an old AGP something-or-other lying around), but I think I'll still try changing screens first.

 

[KenB]

Hi,

By "on-board" I meant a video outlet direct from the motherboard

If you can swap the Video Card to test - this would be a great help.

 

[Pixelkitten]

Hi,

By "on-board" I meant a video outlet direct from the motherboard

If you can swap the Video Card to test - this would be a great help.

Ah, no. As you can see on http://www.asrock.com/MB/overview.asp?Model=939Dual-SATA2 my motherboard has no graphics. It does however have both an PCIe and an AGP port, which simplifies things a lot.

Tried switching screens today, no effect, as expected. Didn't have time to try with another card, will tomorrow.

 

[KenB]

Well we now know that it isn't your monitor.

Let us know the result of swapping the card for a known good one.

 

[Pixelkitten]

After digging through my drawers I found two 128MB AGP cards (found an old ATI card from -97 to, but I didn't try that one). None of them worked, neither on VGA or DVI.

I'm starting to think it's the motherboard that's dead, one of the capacitors looks like it might have leaked, though it's difficult to tell since it's partially hidden behind the CPU fan.
I would totally love to buy some all-new hardware for this computer, but my dad's a cheapskate and I don't have the budget for it myself. Time to start trawling the second-hand market I guess.

 

[Plastic Nev]

Hi, if you do suspect a capacitor, it may be worth while making sure by removing the just the fan to check. A bulging top, or a dried out chemical looking mess underneath are sure signs, and if it has gone, they can damage other components associated with the circuit the capacitor was there for. A small mirror or piece of mirror might help to see better too.

As a side issue, a friend emigrated to Sweden, now a good long time since, so if Dad came from the UK, and is called Ian, give him a kick from me.

Nev.

 

[Pixelkitten]

Hi, if you do suspect a capacitor, it may be worth while making sure by removing the just the fan to check. A bulging top, or a dried out chemical looking mess underneath are sure signs, and if it has gone, they can damage other components associated with the circuit the capacitor was there for. A small mirror or piece of mirror might help to see better too.

As a side issue, a friend emigrated to Sweden, now a good long time since, so if Dad came from the UK, and is called Ian, give him a kick from me.

Nev.

Hi, Nev! The fan is a Zalman S7000C-Cu (http://www.zalman.com/ENG/product/Product_Read.asp?idx=311) and weighs 750 grams, also known as more than a fan for a dualcore from 2005 should weigh. It's held in place by two screws and a flimsy little bracket, so excuse me if I try the mirror idea first, because it's a major pain to remove and replace.

And no, last time I checked my dad wasn't named Ian.

 

[Pixelkitten]

Update

I borrowed a small mirror from my sister and checked that capacitor. It's still difficult to see, but there is definitely some kind of gunk on top of it, it looks like it's leaked out of the capacitor. I started thinking about what else could be wrong other than the cap, and remembered that I don't get any beeps from POST either. It's as if the light is on but nobody's home.

I reassembled the old computer, it seems to work no worse than before, which isn't saying much. It'll have to do until I find something attractive on the second hand market, or manage to nag my dad into buying new stuff.

Thanks for your help guys, we gave it a try at least!

 

[KenB]

It's as if the light is on but nobody's home.

I know some people like that

If the capacitor has sticky resin on top - chances are it has blown.
It is possible to solder in a new one ( using your new-found skills ) but we need to ask ....what caused it to blow in the first place?

I don't get any beeps from POST

This indicates ( normally ) either a PSU or Motherboard problem.

The test is to take all of the cards off the m/b. ( RAM etc )
Disconnect the power connections to the drives
Disconnect the data cables to the drives
Disconnect all external devices
Leave only the 20(4) way cable from the PSU attached.

Switch on.

You should get beeps.
No beeps here indicates M/B or PSU.

 

[Pixelkitten]

What caused it to blow in the first place?

According to Wikipedia this is pretty common for the entire last decade. It's the first time it's happened to me, but I expected it to do so sooner or later.

You should get beeps.
No beeps here indicates M/B or PSU.

Or just that I screwed up when I installed the speaker, or that the speaker was broken. Until I can be sure of the speakers polarity and if it works, that might be the reason why I'm not getting a beep from POST. That still leaves us with the non-existent graphics however.

 

[KenB]

Or just that I screwed up when I installed the speaker, or that the speaker was broken. Until I can be sure of the speakers polarity and if it works, that might be the reason why I'm not getting a beep from POST

This is true.

That still leaves us with the non-existent graphics however.

This is also true.

I was hoping that we could salvage the m/board but it seems that your diagnosis is correct.
It is a motherboard no longer.

If you can get the very same board as a replacement you will have no problems swapping the components over.
A different board would need the Operating System re-installing.

It is possible to get data off the hard drive if necessary - do you have anything that you want on the drive ?

 

[Pixelkitten]

Ken, MBs from 2005 aren't exactly easy to find. My dad agreed with you that I should replace the cap, but when I unscrewed the MB and checked it, I saw it hasn't got any really legible markings. The only thing printed on it is: "(M) 105°C 5 (2) 8S". So all I know is that it has a working temperature of 105°C, just as most consumer capacitors and that it might have a 20% variance in something (That what's the M is for apparently).

The HDDs aren't a problem. The 500GB one is only a year old, and I was planning on reformatting it and start fresh. The old 40GB one only contains documents, which I will transfer to the new one.

 

[KenB]

Hi

20% variance in something

This will be the tolerance - basically how accurate the capacitor is with regards to size ( 100uF could be 80 or 120uF )

Is it an electrolytic capacitor?
click here
and here

The value is usually written on the side in uF

There will be a voltage there too.

What is the make and model number of the motherboard - we may be able to locate one.

 

[Pixelkitten]

Is it an electrolytic capacitor?
The value is usually written on the side in uF
There will be a voltage there too.
What is the make and model number of the motherboard - we may be able to locate one.

Yes, it's an electrolytic capacitor, and as I just said the value isn't written on the side! No capacitance, no voltage, only a temperature and some gobbledygook.

The motherboard is a Asrock 939Dual-SATA2 rev 1.04.

 

[KenB]

They are available:

click here


You would need to check if they would ship to Sweden

click here too

 

[Pixelkitten]

Thanks Ken, at least it's cheaper than a new computer. I'll talk it over with my dad.