You are correct so far.
This is a perfect example of using deductive reasoning based on intelligent thought.
'Armed' with that I can see you will go far in life.
Gateway Support > Gateway 500GR Desktop PC > Main Support page,http://support.gateway.com/s/PC/R/3724/3724nv.shtml
Click on Components in the list.
Scroll down. Under the bold black heading - Motherboards - click on
102007 - Intel (Augsburg) No CPU Motherboard R0
Click on Specifications.
Chipset: Intel 915G Chipsethttp://www.ascendtech.us/gateway-augsburg-intel-915g-motherboard_i_mb4gwaugsburg.aspx
The front of your computer is the Front Panel.
The area of contact pins on the motherboard, that the wires from the Front Panel go to, is the Front Panel header.
In the photo the Front Panel header is marked by the letter S.
Let's go to Intel Support, and download the Product Guide for an Intel D915GAV motherboard,http://www.intel.com/support/motherboards/desktop/sb/CS-012048.htm
Click on the blue -
Intel Desktop Board D915GAV Product Guide - (English) PDF
Scroll your mouse cursor to the bottom/middle of the page, to bring the 'ghosted out' navigation guide into view.
Click on the Adobe PDF icon to the far right.
(When you hover your mouse cursor over it, "Show Adobe Reader toolbar" is briefly shown)
Different design motherboard in the layout of certain headers, and connectors, but same Ol' Front Panel header pinout, Intel uses for 10 pin Front Panel header's.
Whether it is an Intel O.E.M. motherboard, or one they made for a pre-built computer manufacturer.
Front Panel header for Gateway 500GR, is next to the bottom edge of the motherboard, and all the way towards the right.
5 pins across the Top row, 4 pins across the bottom row.
Pins on the Top row are numbered ODD.
Pins on the Bottom row are numbered EVEN.
TOP row; Starting on the RIGHT side going towards the Left;
Pins 1, 3, 5, 7, and 9.
BOTTOM row; Starting on the Right side going towards the Left;
Pins 2, 4, 6, and 8. There is NO Pin 10.
A) Pins 1 and 3 are for the HarDDrive activity LED. (Light Emitting Diode)
Pin 1 is for the Positive ( + ) wire. If the HDD LED is dim when the Harddrive is active, switch the wires around.
B) Pins 5 and 7 are for a Reset switch, IF a Reset switch is used.
C) Pin 9 is N/C. No Connection. Pin reserved for the factory.
(5 Volts DC)
D) Pins 2 and 4 are for the Power On LED.
Pin 2 is for the Positive ( + ) wire.
If the PWR ON LED is dim when the computer is on, switch the wires around.
E) Pins 6 and 8 are for the Power On switch.
F) Again, there is No pin 10.