"Bunny Jump". That's funny.
No, a 4 pin Molex from your Optical or HDD won't work.
You need a dual 4-pin to PCIE 6-pin adapter. It takes 2 separate 4 pin pwer plugs from your PSU and turns them into 1 6-pin PCIE video card power.
And as Sidicas stated, that will only work if your PSU is rated fora 8800's power requirements.
No LANFest 2K8! :(
3DMark Vantage Scores P18241 and X9203
QX9650 @ 4.0 GHz, 4GB Crucial DDR2 @ 920 4-4-4-10
150GB WD Raptor, EVGA Nforce 780i
3x MSI GeForce 8800 Ultras @ 687/1575/2325 Tri-SLI