Hello. I have the below components and have, so far as I can see, installed them all correctly. However, my PC displays nothing and shortly after I power it up, it turns itself off. I'd really appreciate any help with this. Thanks.

Motherboard: N15235 Foxconn G31MXP series

CPU: Intel Core2 Quad (on the chip itself it says)

'05 Q6600
SLACR MALAY
2.40GHz/8M/1066/05A
L725B278

Graphics Card: Nvidia GeForce BFG tech GTX 260 Maxcore 55 OC

Ram: CORSAIR DDR2 (CM2X2048-6400C5DHX)

Power Supply: X-Power ATX-600TD

Again, any help with this would be really appreciated. Thanks.I am on the same boat with you. I am certain I installed everything correctly. Do you GET any beeps? I do not and cannot figure out how to hook it up to hear them. The plug is not plugged in on the motherboard above the power and reset switch for a speaker.Welcome to the forums, both of you.
Adanniels, it'd probably be best for you to start a new topic, as your issues may be the same but could be completely different.
Firstly, are all these PARTS new or used?  if used, do you know for sure that they WORK?
Powering down shortly after the system is powered on would indicate possible issues with overheating - check your HEATSINK is seated properly - or power.