Windows 7 Missing Drivers

I just upgraded to Windows 7 x64 RC (Build 7100), and I'm missing some drivers. I've looked all over the place, and I don't know where I'd find them. My device manager says I'm missing drivers for:
"SM Bus Controller"
and two other
"unknown device"

My motherboard is an Asus P5ND2-SLI, and as I bought it second hand, I don't have the driver CD with it. I went to the drivers on the asus site, but I don't know which I'm meant to install, and many of them didn't work that I tried.

I tried to use a program I had luck with previously called "unknown device identifier", but it gave me an error and wouldn't give me a list of all my computer parts.

So, I used everest to check out my computer, and it doesn't know my motherboard model or my bios, so I think it's missing all the drivers, I'll try to update whatever I can.

*edit*
Tried to update the bios, but it said that I needed to check which version I'm using (64/32 bit), and closed. It didn't have an option for 64 bit.

So, I got one, the nForce4 drivers. One is a gameport thing, which I don`t think I`ll worry about seeing as I don`t have a game pad.