So, just this weekend, I gathered all sorts of parts I bought on newegg and compiled them into what might be called a computer. Unfortunately, every time I start up the system, my monitor displays "Check your cables" and my speakers emit a loud Morse-code-like beeping noise. I know the beeping means that something is wrong with my hardware, so I looked up what it could mean. As far as I can tell from all the various sources, a long beep followed by two short ones stands for a video card problem (which explains why my monitor isn't getting any input). I have tried placing the video card in both of my motherboard's PCIe X16 slots, and have gotten the same results. I even tried a different video card in each of the slots to no avail. The problem isn't with my motherboard, as far as I can tell -- the CPU fan is running and the green power LED is lit up. The problem isn't with the power supply because the CD drive, which is hooked up to the same line as my video card, lights up. The only conceivable problem at this point is a small, white, two-pronged connector near the base of the card (it looks a lot like the fan connectors on the motherboard, but it has two prongs instead of three). Could this be a required connection? If it is, then why wasn't there any cables included in the packaging for it?

Motherboard: A8N-SLI deluxe

Video card: GeForce 7950GT (passively cooled)