Dead, dead, dead! How to figure out why?

[Odyssey]

Circumstances are: daughters' Dimension 4500 (XP) in England and I am in USA. One morning nothing happened when startup was attempted. The diagnostic lights on the back do not light up at all.

Each card has been removed and a startup attempted with the respective card out. Nothing.

HDD's were disconnected (power and ribbon) also. Still nothing.

It was assumed that the power supply died, so we ordered and replaced the original with a new one. No cigar!

Shouldn't the fan operate if the computer is switched on? Given that it is highly probable that the problem is not the power supply, if the fan does not start, is this an indication that the off/on switch is dead?

Would a dead clock battery result in no sound, no action?

Can anyone suggest further tests to try to find out what the point of failure is? Any early responses much appreciated as there is work on the HDD that is badly needed.

TIA.

 

[electronicsfreak]

Connect power supply and motherboard (processor and fan included) and nothing else. Disconnect the power switch, short the 2 terminals for just 1 second that the power switch was connected to. If it turns on your switch is bad, however if it doesnt your board is either shorted or dead. Check on the board for swelling or enlarged capacitors. It might also be possible that your processor itself is dead instead of the motherboard but if it does not turn on as above id say most likely motherboard.

 

[SPV]

Yes I would expect the dan to operate as soon as the board powers up, regardless of the clock battery.

Your post doesn't mention trying a different power lead and power socket, but you may have done that already.

Failing that, is there a fuse on the system board?

Just trying to think of simple and/or cheap things to check before it starts looking expensive.

 

[ski]

No fans will run by just turning placing the power supply's switch in the ON position. The computer has to be turned on in order for the fans to run.
However, the motherboard'a standby light(assuming it has one) should turn on when just the PS's switch is turned on.

Make sure the PS's switch is in the correct voltage position.
If that's ok and a surge arrestor is used, then bypass the SA, and connect the PS's cord directly to the wall outlet.
If the system works, then the SA is bad.

If that does not work, then connect the system to a different outlet.
If no luck, then try an outlet in a different room.

 

[Odyssey]

Had to leave the house for a spell, so will deal with all the most appreciated suggestions in order:

Connect power supply and motherboard (processor and fan included) and nothing else.
-Will request them to do this.

Disconnect the power switch, short the 2 terminals for just 1 second that the power switch was connected to. If it turns on your switch is bad, however if it doesnt your board is either shorted or dead.
-Excellent suggestion, but not sure that my daughters' level of competence/confidence will permit. Will explore with them via Skype.

Check on the board for swelling or enlarged capacitors.
-Will ask daughters to havalook.

Yes I would expect the dan to operate as soon as the board powers up, regardless of the clock battery.
-Problem is absolutely nothing happens when switch on front of case is turned on. One daughter mentioned that the switch doesn't seem right, seems hard to press and doesn't "click". I'm thinking that the front switch may be wheels up?

Your post doesn't mention trying a different power lead and power socket, but you may have done that already.
-She took the lead from the UPS and plugged it directly into the Dell PS, then plugged it back into the UPS to double check and the lead/outlet were OK. So power is getting to the Dell Power Supply for sure.

Failing that, is there a fuse on the system board?
-What type of fuse should they look for? I cannot recall seeing one on that computer (or any computer for that matter, but I may have just been overlooking.)

Just trying to think of simple and/or cheap things to check before it starts looking expensive.
-My kind of solution!!!!!

No fans will run by just turning placing the power supply's switch in the ON position. The computer has to be turned on in order for the fans to run.
-Sorry, may have been some confusion here. I meant that when the power switch on the front of the computer was turned on, the fan should operate, even if the MOBO or CPU is dead-No?Yes?

However, the motherboard'a standby light(assuming it has one) should turn on when just the PS's switch is turned on.
-Again, not sure there is one, but will consult manual

http://support.dell.com/support/edocs/systems/dim4500/9n756bk0.pdf

and see if I can see anything and will ask daughters to havalook also.

Make sure the PS's switch is in the correct voltage position.
-It is an auto(voltage)switcher with no off/on switch on the PS

If that's ok and a surge arrestor is used, then bypass the SA, and connect the PS's cord directly to the wall outlet.
If the system works, then the SA is bad. If that does not work, then connect the system to a different outlet.
If no luck, then try an outlet in a different room.
-see (UPS) above.

Great suggestions and comments. Many thanks and any other are also welcome as result of above input.

 

[Odyssey]

It appears to have one (see page 69 of manual):

http://support.dell.com/support/edocs/systems/dim4500/9n756bk0.pdf

so now awaiting daughter feedback (UK 6 hours ahead of CST)

 

[Odyssey]

It seems that the front on/off switch does not "click" on and off as front on/off switches normally do. Apparently when one tries to "click" it, there is just resistance and no movement. I am increasingly convinced that the switch is faulty. To confirm, would like to short the switch leads with the PS plugged in, but cannot figure out how. The entire front panel wiring is a multi-lead flat cable which comes to a "multi-pin" plastic connector something like the IDE connector on an optical or HDD (see manual on page 69-top right corner of mobo):

http://support.dell.com/support/edocs/systems/dim4500/9n756bk0.pdf

Since I am here and the computer is there, can't follow the leads (which disappear behind the front panel anyway) and cannot find which pins are to what in the manual.

The insert that the switch appears to be mounted in will pop off if pulled up revealing the switch, but unfortunately the insert is purely cosmetic and the switch is firmly mounted in a piece underneath the insert so we still can't figure out how to remove the switch or even see the back of it.

Does anyone know how to extract it and/or which pins (either on the switch itself or the mobo pins (J60H1)) should be shorted to simulate pressing the button.

Help!

TIA

 

[electronicsfreak]

What you need to do is look on the motherboard find its name and model number and find the manual for it. Also if you look closely you might find markings on the pins. Like pw+ pw- . If not look up the info like I stated and find the manual

 

[Odyssey]

Excellent suggestion and I will ask the daughters to try to find the name/mod # and/or the pin markings (BTW, is pw+pw- what they should be looking for?). The latter might be a little over their heads, but may have some luck with the former.

 

[electronicsfreak]

Yeah that is what your looking for, those are the 2 terminals that control the on. When a switch is pressed those 2 leads are shorted for a second or 2 and it activates everything and the computer starts up. The reason you only cross them for a second is if you cross it for to long its like holding the power button down for 4 seconds or longer, the computer will simply turn back off. Anyways those are what you are looking for.

 

[Odyssey]

Very helpful. Many thanks.

 

[ceh4702]

What if the CPU burned out?

The Switch can also be mechanically or elictrically malfunctioning.

Motherboard could be grounding out. i.e. circuits touching metal.

Power plug could have a problem.

Elec Circuit could be bad.

What is the power there? is it 220 or 110?

What is the setting for 220/110 on the power supply?

Are you using a converter plug and if so is it working?

If you do not like my post feel free to point out your opinion or my errors.

 

[Odyssey]

CEH4702, all of the things you mentioned are possibilities. Without another computer to try the CPU in, how would one determine until all other possibilites exhausted? Also don't know how to test the switch (which sits on a small circuit board behind the front cover)

The power there is 220 and the PS is set to 230 and we know that power is good at the outlet and that the power cable is delivering power.

They are not using a converter plug as they have local cables.

If you do not like my post feel free to point out your opinion or my errors. On the contrary, good points and much appreciated. If you can guide us to a test for the CPU and the off/on switch, it would be great.

 

[electronicsfreak]

best way to test a switch is if you have a meter. Switch it on continuity and put one lead on each wire. Push the button in and hold it. If it gets continuity its good. If it doesnt its bad. If it stays taht way without being pressed in or after you let it out its bad.

 

[BadFrog]

Any feedback on the state of the standby light? Is it on or off? If there is no led's lit up anywhere on the board I would bet that the motherboard is bad or shorted. If the standby light is lit then I would say there is a good chance the switch is bad. The front panel switch connector (J60H1) is where the two leads are that you need to short for powering the system on. If its not labeled the easiest way is to find which color wires are coming out of the switch and trace them back to the connector.

I realize you are troubleshooting this third party via your daughter which makes some of the suggestions not too practical. Good luck and I hope some of this helps.

"Once you can accept the universe as matter expanding into nothing that is something, wearing stripes with plaid comes easy"
Albert Einstein

 

[Odyssey]

Thanks to both.

If I understand the first post, this would be an ohmeter? Trouble is that the switch is soldermounted to the circuit board that is is mounted on so no wires to connect to.

Also the leads coming to the motherboard are flat grey multi-threaded cable (looks like a small IDE cable) so no colours to guide us.

No lights of any kind, so perhaps it is the mobo. Having just bought a new Dell power supply, it probably makes sense to stay with Dell, but a replacement board bought direct from Dell would probably cost more than the entire computer is worth.

Any suggestions on where to get a replacement? (Nothing showing on Ebay)

 

[BadFrog]

Here are a few. Never bought from either so research first.

http://www.impactcomputers.com/2p997.html

http://www.streetprices.com/Electronics/Computer_Hardware_PC/Motherboards/SP3307382.html

http://www.circlecomputer.com/Dell_Spare_Parts2.htm

"Once you can accept the universe as matter expanding into nothing that is something, wearing stripes with plaid comes easy"
Albert Einstein