Asus P5G41T-MLX won't boot, error code 26

Hey,

I've been trying to get a computer to boot without success:
MB: Asus P5G1T-MLX (socket 775)
CPU: E6750 dual core

Board won't boot, error diagnostic pci card shows error "26".

I think its amibios.
I have attatched a screenclip of a manual stating what the error means, eventhough I have no idea what that is.

Things I've tried:
1. changing RAM stick position
2. use different RAM stick.
3. clear cmos battery
4. clear bios with reset jumper

Any suggestions?

Thanks