weird problems with board..

Ok, I have a N650SLI-DS4 mobo, and I get some weird problems.

First off, I had all my components working and running vista on a evga 680i board, but I RMA'd it because of some dead dimm slots.

If I put the vista cd in, I get this:

Verifying DMI Pool Data .......
Boot from CD/DVD :
DISK BOOT FAILURE, INSERT SYSTEM DISK AND PRESS ENTER

If I try the gigabyte disk, I get the same, but a few times, it enters some utility which gives me the option to backup or reboot. I try backup and it says not enough space on HDD.

I know all my components work, because I had them working on my 680i.

The bios is detecting the HDD and DVD drive, and I set dvd to boot before HDD..

I also periodically get a black screen where it gives me the option to start windows normally, safe mode, last good config..

ALL THIS STUFF IS COMPLETELY RANDOM AND HIT OR MISS!! MAKES NO SENSE!! I REPEAT THE EXACT SAME THING AND GET DIFFERENT RESULTS!!

Shouldn't I have the same options everytime???

One other thing I should note is I have a OEM vista cd, and I read somewhere that once you install it on a mobo, it can't be installed on another mobo. Could this be the problem? It doesn't seem to make sence that I'd be having problems booting from both cd's though...

Oh I should also note that when I pressed the power button 1 time (didn't hold to shut down, just pressed) at the boot error, press enter screen, I got a long continuous beep until I turned off the power.