DOA? New build

[curt42]

Here is my new computer build...
CPU: Core 2 Duo 6850 box
Mother board: nForce 680i SLI
RAM: 4 x 1GB DDR2 PC 6400
GPU: PNY GeForce 8800GTS PCI Express 640 GDDR3
HDD: 2 x 500 GB SATA/300
Optical: 18x DVDRW
PSU: Thermaltake 600
OS: Windows Vista Home Pro
Case: Antec Nine Hundred
Display: Samsung 19" LCD DVI connection

I installed everything after reading each instruction book. I powered up and nothing appeared on the monitor. The LCD panel on the mobo indicated an error message 7F (Check POST error and display them and ask for user intervention).
I rechecked the connections and tried again. Same results.
I pulled the mobo out on the bench, removed all but one RAM strip, HDDs, Optical drive. Same results.
I pulled the GPU (along will everything else). Same results.
I read the thread on trouble shooting. I am not getting to see anything on the screen. The only error message comes from the 2-character LDC on the mobo.

This is my first full build of a computer and find this very frustrating. I am about ready to take it to a "Geek" service in town. Any suggestions.

My goal is to have a computer that I can run flight simulator(s) along with everything else I normally do on a computer.

Help?

[Cricket]

What brand motherboard are you using?

Do you have all the necessary power connectors plugged into the motherboard?

Cricket

[curt42]

I installed the nVidia nForce 680i SLI motherboard. The manual shows (and I installed) three different power connections... a 24-pin ATX power, an 8-pin ATX power, and the auxiliary 4-pin power. I hope I didn't miss other connections.

Do I have to run GPU's in pairs, or will my single 8800 GTS w/ 640 mb do the trick for running FlightSim X?

[Sirkwa]

A single 8800gts will be more than enough to push FlightSim X. It only requires a 32MB Video card with DX 9