That would be connecting a jumper wire, from the Green wire to ANY Black wire, in the 20 or 24-pin ATX main power cable's connector.
If this problem is in direct relation to a Dell E210882 motherboard, it uses a 24-pin ATX main power cable,http://en.community.dell.com/support-forums/desktop/f/3514/p/19298234/19565862.aspx#19565862
Example of a 24-pin power cable, and it's respective connector,http://www.playtool.com/pages/psuconnectors/connectors.html#atxmain24
The Green wire is the Soft Power On wire. (Abbreviated as PS_ON)
ANY Black wire is Ground wire.
With the 24-pin ATX main power cable plugged into the motherboard, and the power supply,(Computer), plugged into power, the jumper wire is inserted into the back of the 24-pin ATX main power cable's connector.
Looking at the photo to the far right in the link, shows the ATX main power cable plugged in.
Where the wires go into the connector is the BACK of the connector.
One end of the jumper wire, goes down into the socket hole with the Green wire, RIGHT NEXT TO THE WIRE.
The other end goes down into a socket hole with ANY Black wire in it.
The end of every wire going down into the ATX main power cable connector, has a metal terminal end.
This metal terminal end is pretty far down into the connector, from the backside of the connector.
For this reason the jumper wire MUST go down into the socket hole, far enough to touch the metal terminal end.
The most widely used jumper wire is a paper clip.
The paper clip is straightened out, then bent into a U-shape. Black plastic electrical tape is applied to the center of the U shape.
This taped area is for your fingers.
(One wrap of black plastic electrical tape will insulate you from 600 Volts DC)
The 'legs' of the U-shaped paper clip then go down into the socket holes.
The voltage is 5 Volts DC.
Two D cell flashlight batteries produce 3 Volts DC.
The voltage is VERY low, but there may be a small spark.
Warning you in advance.
Power supply comes on?
You have a bad Power On switch.
Power supply does Not come on?
You have a bad Power Supply.
For additional questions, or to clarify anything I have stated, please post in a Comment.