Newly Built Computer Won't Post...sorta

[Eternium]

Went through all the troubleshoot FAQS, but this problem doesn't seem to match up with any of those.

Computer turns on, all fans will run, PSU is on, all mobo lights are on, but after the mobo title screen thing, the only thing that will load is a hyphen (_) and nothing happens. Switched out RAM, nothing changed. Made sure all connections were in place, but still no change. Anyone know what else I could try? (Note, it seems it will detect a keyboard being plugged and if you hit any key, the hyphen will break to a new line, but nothing happens beyond that.)

On a less pressing note, the case's "power" LED cord is too big for the socket the mobo gives it (it's a 3-pin while the mobo's is a 2-pin). Is there a way around this, or do I just have to deal with it?

Here's the specs:
MSI 870-G45 AM3 AMD 770 ATX AMD Motherboard
AMD Phenom II X2 555 Black Edition Callisto 3.2GHz Socket AM3 80W Dual-Core Desktop Processor
EVGA 512-P3-1240-LR GeForce GT 240 512MB 128-bit DDR5 PCI Express 2.0 x16 HDCP Ready Video Card
SAMSUNG Spinpoint F3 HD502HJ 500GB 7200 RPM SATA 3.0Gb/s 3.5" Internal Hard Drive
G.SKILL Ripjaws Series 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model F3
OCZ Fatal1ty OCZ550FTY 550W ATX12V v2.2 / EPS12V SLI Ready 80 PLUS Certified Modular Active PFC Power Supply
LIAN LI Lancool PC-K58W

 

[MindoverMaster]

The (_) is because of a corrupt Windows file. Can you get into safe mode?

For the power led cord, you have to change the cable from the 1st and 3rd pins to the 1st and 2nd or 2nd and 3rd, whichever way it goes in your motherboard. Try getting a converter cable from 3pin to 2pin.

 

[Eternium]

That's weird, it's a new hard drive, and it still does it even without the hard drive plugged in.

I'll try the idea with the led.

 

[Win2kpatcher]

I hate those dang little jumpers...All I ever hookup is the power button jumper and thats it..haha. As for the boot issue...this usually means its having issues finding the boot device with a loader on it...do you have an OS installed on the new hard drive? The easiest way to determine if it is hardware or an OS issue is to see if you can boot into a knoppix live environment...this is a bootable linux OS CD...set your boot priority to put the CD drive first...if it boots ok to the knoppix CD we at least know hardware is ok and its something with the way the OS is installed. Are you able to even boot to a Windows CD? Did you perform a clean install?

 

[MindoverMaster]

I would much more suggest Ubuntu, but yes, a Linux Boot-CD