POST problems….

I’ve just built a new system, and I’m getting quite the annoying problem.
I’m running an ECS K7VZA rev 1.0 mainboard with a Duron 900 processor. I’ve got 256MB of PC133 RAM installed, and a Western Digital 40GB HDD, along with ATI’s amazing Radeon 64MB DDR AGP card. Unfortunately, in the POST, I’m getting one long beep and two sort beeps. I’ve just barely built this system, and it’s the first time I’ve attempted to boot. It’s been a while since I’ve had an error like this, so any suggestions would be greatly appreciated! Thanks!