computer won't power on

allenkt · 02-25-2007, 05:50 PM

I have a Dell Dimension (3000 series I think) and I'm trying to find the point of failure.

A few days ago when I turned it on I got a message saying it couldn't find the hard drive. I did a cold reset and then it powered up. But the next day I got the same error message and couldn't get it to start. I thought maybe it was a bad hard drive so I went to boot to a disk (SpinRite) but that didn't work either....still wouldn't boot. I went into the bios and discovered that according to my bios I didn't even have a CD drive installed. Weird....maybe no power getting to the drive?

My next step, just for the heck of it was to take off the cover and clean it out. We have a dog and a cat so hair tends to build up. I vacuumed it out and blew out the rest. I even took the heat sink off the CPU and made sure there wasn't anything between the two somehow.

But when I plugged it back in I got nothing. The light was coming on on the motherboard but when I hit the power button nothing would happen. My first thought was the power supply. Seemed to make sense if it wouldn't power up and the CD drive maybe wasn't getting power. So today I replaced the power supply but that didn't change anything. Still getting the light on the motherboard and on my NIC card but it won't even go to the POST. No fan, nothing.

So what is the next possible point of failure? When the power comes out of the power supply where does it go first? I haven't put a multimeter on the wires coming out of the power supply but I'm pretty sure it's putting out power since the light is on on the motherboard.

Does this sound like a bad motherboard? Trying to figure out why the fan doesn't come on but I'm not sure where the fan gets it power.

Any thoughts? At this point it's probably cheaper to just replace the computer but I'd like to fix it or at least figure out what is wrong.

Kevin Larrabee · 02-25-2007, 06:31 PM

Its either motherboard or Power supply. It is also possible you fried the motherboard if you touched it when you opened the case and cleaned it.

Most likely, it will be cheaper to just replace the thing.

allenkt · 02-25-2007, 06:35 PM

Quote:

Originally Posted by Kevin Larrabee

Its either motherboard or Power supply. It is also possible you fried the motherboard if you touched it when you opened the case and cleaned it.

I thought about that since it's been very dry here and static electricity has been a problem but I tried to be very careful when I cleaned it and did wear my grounded wrist strap.

And yeah, I'm sure I'll just end up buying a new computer. It's an older computer (a couple years old) and not really worth replacing the motherboard.

Phaedrus49er · 02-25-2007, 06:52 PM

I had the same issue with my first (and only) Gateway back in 1998. After a few years, I started getting "hard drive not found" errors and such, and it ended up being bad heads on the hard drive itself, oddly enough. However, that also caused other components to either be unpowered or simply unrecognized. I got around it a couple times by re-installing Windows, but ultimately I got a new hard drive (at first), then ended up building my own machine.

FishrCutB8 · 02-25-2007, 07:09 PM

I think I found your problem...

Mark57 · 02-25-2007, 07:43 PM

If it's at all possible, move your hard drive to another computer and see if it boots up. If not, try putting the hard drive from that computer in your pc and see if it boots. If the first one is NO and the second is YES, your hard drive died.

If the first one is YES, check your mother board. We've had problems with some Dells, mostly Optiplex 270s but other models could be affected. Look at the capacitors (one inch or so tall black cyliders with a silver top), if any of them have a convex (popped up) or discolored top they're blown. Call Dell and see if they'll replace it for free.

If all of those look good, it might be a power supply. You could take it in to a computer repair shop, they probably won't charge much for a diagnostic check to tell you for sure what's wrong.

allenkt · 02-25-2007, 08:18 PM

I'll try swapping out the hard drives tomorrow and see what that does for me. Although if I can't even get to the POST could it still be the hard drive? Right now I can't even get to the bios setup.

The capacitors all look fine and I replaced my power supply today but that didn't help. I'm leaning towards thinking it's a blown motherboard but I'll try the hard drive in another computer tomorrow just to see what happens.

Frank.S · 02-25-2007, 08:38 PM

Deal is well known for putting in mobos that are not good enough for the components. You could buy a new mobo that will work for pretty cheap, its not all that hard to install.

Lost Dog · 02-25-2007, 09:10 PM

When you went into the bios, were you able to manually set it to see the CD or harddrive.

The battery for the bios might be bad.

allenkt · 02-25-2007, 09:16 PM

Quote:

Originally Posted by Lost Dog

When you went into the bios, were you able to manually set it to see the CD or harddrive.

The battery for the bios might be bad.

No, I couldn't set it to recognize either. It simply said they did not even exist. And I did switch out the CMOS battery just for the heck of it but that didn't help any.

Ogedei · 02-25-2007, 09:21 PM

Ram is always a possibility, it can do weird stuff.

By fan not spinning do you mean your CPU fan? If so, it coulda gone south as well due to heat.

Hard to pinpoint without known good components to swamp in.

Lost Dog · 02-25-2007, 09:21 PM

Mother board, sounds like. They are cheap, though.

allenkt · 02-25-2007, 09:32 PM

Quote:

Originally Posted by Lost Dog

Mother board, sounds like. They are cheap, though.

I suppose I could try swapping out the MB....that's about the only thing I have never changed on a computer before. Not like this is a nice computer that I have to salvage but I'd hate to let the computer think it won

Jeff Rage · 02-25-2007, 10:16 PM

Are there diagnostic lights on the back, labeled A-D? If so are any amber? Are you hearing a sequence of beeps when it starts up? If so, what is the pattern?

Is the Dell mobo propriatary in some way that you can't swap it with another brand mobo?

Ogedei · 02-25-2007, 10:46 PM

Quote:

Originally Posted by Jeff Rage

Are there diagnostic lights on the back, labeled A-D? If so are any amber? Are you hearing a sequence of beeps when it starts up? If so, what is the pattern?

Is the Dell mobo propriatary in some way that you can't swap it with another brand mobo?

diagnostic lights? wtf??

Jeff Rage · 02-25-2007, 11:05 PM

Quote:

Originally Posted by Ogedei

diagnostic lights? wtf??

They have them on the Optiplexes, not sure about the Dimensions.

Ogedei · 02-26-2007, 06:01 AM

Crazy.

Back in my day we didn't have none of those new fangled diagnostic lights..

FishrCutB8 · 02-26-2007, 07:18 AM

Quote:

Originally Posted by Ogedei

Crazy.

Back in my day we didn't have none of those new fangled diagnostic lights..

Thankfully we've moved past the age of chalk and the abacus....

ShannonB · 02-26-2007, 08:42 AM

Quote:

Originally Posted by FishrCutB8

Thankfully we've moved past the age of chalk and the abacus....

Shhhh, don't tell him. Before you know it he'd find out about internet, and then we'd all be in trouble.

Erika · 02-26-2007, 08:47 AM

If you replace the motherboard they will probably make you buy it with a new power supply so you are out that cost again. It is getting expensive.

What you describe has always been motherboard and blown capacitors for me, three times now but on different computers thankfully.

laxcdn · 02-26-2007, 09:16 AM

Try unplugging everything inside and then try turning it on. This way you have no drain on anything and if one of the components is bad it can sometime cause it not to turn on. After that try moving the drive to another pc. If you get another on and the drive is fine then you can put that drive in to get your files off.