You did some damage when you had the computer's case open, probably by touching the 
electronics without taking proper precautions.

You must not touch *anything* inside a computer's case without first taking anti-static 
precautions, to avoid static electrical damage to the delicate electronics inside.


You need to follow these simple guidelines, always:

1. Shut down the computer, and SWITCH OFF the mains power at the wall socket. This 
is an ESSENTIAL safety precaution!

2. If the computer has a 3-pin mains plug, DON'T unplug the computer from the wall 
socket. The 3rd pin is an Earth connector, which grounds the chassis (the metal case) 
of the computer; you need to leave that connected. Any dangerous voltages are INSIDE 
the (sealed) power supply unit, where you can't get at them.

3. Immediately before touching anything inside the computer, touch an unpainted bare 
metal part of the chassis (the casing) with your bare hand. The metal casing is connected 
to earth (through the wall socket), so your body is thereby earthed, draining any 
static electricity from your body: half a second and it's gone. Do this every time, 
because as you move about the contact with carpets and clothing will generate further 
static electricity on the surface of your body.

4. If you use a tool (e.g. a screwdriver, or vacuum cleaner), touch a bare metal 
part of the tool to the bare metal of the computer's casing before you touch it to 
anything inside the computer.

5. If your computer does not have a 3-pin mains plug (i.e. if it has a 2-pin plug), 
earth yourself by touching unpainted bare metal on a central heating radiator pipe 
or cold water pipe instead, as those are normally connected to ground. Do this for 
yourself and for your tools.

6. Don't let any part of your clothing touch anything inside the computer, as clothes 
can carry a large static electrical charge. It is therefore best to roll your sleeves 
up.

7. While working inside the computer don't scuff around on the carpet, or slide in 
and out of a chair - as this will cause a build up of static electricity.

8. You must also apply these precautions when handling any component that you unplug 
from the computer: such as a hard disk, or a PCI card, or a RAM memory module.

NB: The safest procedure is to rest your bare forearm on an unpainted bare metal 
part of the casing continuously whilst working inside the computer, thereby leaving 
both your hands free.


From your description of the damage, it sounds like you may have fried the motherboard. 
You seem to have a monitor and a hard drive that are receiving power, but nothing 
is happening. Monitor, hard drive, and power supply unit would therefore appear to 
be in working order.

If you have a dead motherboard, no information or instructions can travel between 
keyboard and hard drive, or between hard drive and monitor screen. If that is your 
situation, you will have to buy a replacement motherboard.

As that is an expensive option, and one that is fraught with problems, consider having 
this hardware fault fixed by your local computer store. If you insist on tackling 
it yourself, on a DIY basis, my tip is to try to buy the same model of motherboard 
that you started with, as this reduces the problems you will face.

Motherboards are *not* interchangeable. A different type will be bound to be incompatible 
with at least some of the other hardware inside your computer. Older motherboards 
are sold on E B A Y. Or try a Google search. In both cases, search on the model number 
of the m/board.

The model number of your m/board will be printed on the board, usually in large white 
lettering near the PCI expansion slots.


Ed







On Thursday, April 19, 2007 at 6:24 am, Charles wrote:

>I have a Dell Dimension 4100 with Windows Me as the OS. Upon bootup the monitor 
does 

>not display anything, it seems to be ok though, since when I disconnect it I get 

>the RGB onscreen error. When I click the power up button on the pc the green light 

>on the swithch is not on (it always lit previously). The pc is not showing signs 

>of Hard drive malfunction, no beeps, whirrs, clicking etc., the little hard drive 

>still lights up during bootup and goes out, indicating HD access. I had opened the 

>unit to clean and vacum the dust out. I thought I was fairly careful. I suspected 

>the video card and re-seated it with no succes, I've yet to replace it though . 
Could 

>it be the power source or the power switch (unusual that it no longer lights up)? 

>Can someone please provide some insight, thanks. 

• Reply or follow-up to this message

• Search this forum
• Start a new thread on a different subject

• Report abuse of the forum