Member Avatar for Katherine692008

My dimension 5100 was working just fine.
Then, just for the hell of it I opened to tower to check the RAM, (was going to upgrade RAM but didn't need to).

After I closed the tower my machine would NOT come on!:@
I pressed and Held the Power button in the front but NOTHING.
No sounds, No power, NOTHING.

But after opening the tower back up I did notice when I plugged the machine on the green light on the motherboard came on.:-/

I'm not sure whether I should replace the MOTHERBOARD :( , or the POWERSUPPLY :( ,
Or do something else:'( .

Please help

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  • Latest Post Latest Post by danieljbryan

Dani AI

Generated

Quick, practical diagnosis for a Dimension 5100 that shows the motherboard LED but won't start (builds on points from , and others).

A steady green board LED usually means the PSU standby rail is present, but the main power rails are not being engaged. The fastest, low-cost tests that will isolate the fault are: bypass the front-panel board, verify the PSU can be forced on, and do a visual inspection for shorts or burned parts (use the sequence below).

  1. Bypass the front-panel board (quick check)
  • Unplug AC. Open the case and locate the small ribbon cable that goes to the tiny front-panel PCB (the board described). Carefully unplug that ribbon from the motherboard.
  • With the PSU plugged in, momentarily short the two power-switch pins on the motherboard with a small insulated screwdriver to simulate the front power button. If the system starts, the front-panel PCB or switch assembly is bad.
  1. Test the PSU (safer method: swap)
  • If shorting the PWR pins does nothing, test the PSU by swapping in a known-good ATX supply (recommended) or, with care, use the PS_ON-to-ground paperclip test to see if the PSU fan and main voltages come up. If the PSU runs but the board still does not, the motherboard is likely at fault.
  1. Visual inspection & the “white flash” case
  • Look for burnt traces, melted plastic, leaking/bulging capacitors or scorch marks on both the small front PCB and the motherboard. A visible flash (as saw) often means a shorted component — stop and consider professional diagnosis if you see damage.

Safety notes: always unplug power before touching components, avoid shorting anything except the intended pins, and if the machine is under warranty stop and contact Dell. If these tests are uncomfortable, a quick shop bench-test (swap PSU, test power pins) will find the faulty part within minutes.

Recommended Answers

All 11 Replies

Member Avatar for jbennet

You cant replace the motyherboard on dells. They are nonstandard.

Take out the ram and put it back in . Make sure it is in properley.
Secondly, unplug the PC from the wall and leave it for half an hour. Hold the power button for a while while it is unplugged.

Then try starting it up again.

You did protect yourself from static discharge before opening the case, right?

Member Avatar for Katherine692008

I thought SO :(. Would you know WHY I can't replace those motherboards?

I'll try taking the RAM out. Not too sure that would do anything but I will try that.

Do you think static discharge could have done this?

Member Avatar for jbennet

The case and motherboard are nonstandard, because they dont use standard front panel connectors. Normally they are just wires with pin headers, but the dells use a small circuit board which provides the power switch, hd activity light, and diagnostic functions. This is very uncommon and connects to the motherboard via a strange IDE-type ribbon cable.

Ive got a 5150 (e510) and my dad has an e520

The PSU in my 5150 is replacable with a standard one, but a new one will be a very tight fit + not very secure.

Yes, static could have done it. And i reccomend taking the ram out because my dads E520 has a similar issue. It would not stop beeping because the ram wasnt seated properley.

Member Avatar for Katherine692008

Thanks for your fast replies. :D
I'll take all the RAM out later.

Since static could be the culprit. Do you think the "RAM fix" would still help?
Hopefully I don't have to buy another desktop.

Member Avatar for Katherine692008

That smile should have been a BIG CHEEESE!

Member Avatar for jbennet

If it waqs static, the machine is probably dead

didnt you wear a wrist strap?

Member Avatar for Katherine692008

actually NO :(
I didn't think wearing one would make a difference.
Will any wrist strap do?
Or should it be a certain kind?

This really does suck. :'( :@
I'm glad I have another desktop

Member Avatar for jbennet

one of those antistatic wriststraps which you clamp to a ground. a good idea to wear one when working on pcs.

Member Avatar for caperjack

i have been working on computers for 9 yrs now ,i don't own a wrist strap and have never fried a stick of ram or a motherboard by not wearing one .unplug power source ,hold down power button and , as long as you ground yourself to the metal case first ,by just simply grabbing the side of the case you should be alright.
=
when you opened the box to check the ram did you take it out ,if yest take it out again and replace it like jbennet said ,also check to make sure you didn't knock any wires /cables loose,especially the front panel connection

Member Avatar for microtech-nb

i have been working on computers for 9 yrs now ,i don't own a wrist strap and have never fried a stick of ram or a motherboard by not wearing one .unplug power source ,hold down power button and , as long as you ground yourself to the metal case first ,by just simply grabbing the side of the case you should be alright.
=
when you opened the box to check the ram did you take it out ,if yest take it out again and replace it like jbennet said ,also check to make sure you didn't knock any wires /cables loose,especially the front panel connection

I agree with this - I've been working on PCs for 10 years and never used a wrist strap. Besides that, I have this same system having the same problem and have NOT been inside the case.... Any other ideas?

Member Avatar for danieljbryan

My Dell Dimension wont power up. Was ok but started to get difficult to power up. now wont start at all .I have taken the front cover off and there is a small white flash when I push the starter button can I replace this switch mechanism and if so how .I see its connected by a ribbon to the motherboard how to I get at the switch.

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