Help! Power problems

I recently bought a gigabyte ux58-ud3r board which has the 2x4 12v connector in addition to the 24 with an i7 920 chip. I pulled my old PSU which is 500w i thought would be plenty, but it doesn't have the 2x4 connection. it seemed to power up, but I never got a display or bios. They made it seem optional, but is that 2x4 12v connector necessary in order to start a comp with an i7 chip? Very new at this, just wanted to save some money and learn to build my own. oh yeah, ram is 6gb (3x2) ddr3 1280.

The mobo needs at least a 4 pin cpu power. If the psu has the 8 pin, then that is a bonus as mentioned above. But at minimum it needs the 4 pin cpu power.

You don't need spacers. Try it with the mobo outside the case on a piece of cardboard.

As pointed out, 4 Pin should work, 8 Pin connection should only be required when pulling more than 120 W, Which a stock i7 920 should be below (do not confuse with max TDP). I think you will find that all 4 +12V sockets on the MB are tied together and all 4 grn sockets are tied together.

badge - Not positive, but I think the connection is keyed to that the PSU connector should only go in one position ( except for gorrillia man)
Added
you are correct in that it could fit top or bottem Halve as plug is shaved at both corners

OP - MAKE SURE that you put the 4 Pin in correctly (You currently have, as incorrect would fry psu and/or MB.