I confirm the Intel(R) Core(TM) i7-970 Processor does come with 6 physical cores, which, when hyper-threaded, they could sum up for a total of 12. Hence, I'd next recommend the following:
1. Ensure the processor cores are detected fine in BIOS.
2. If the BIOS does see the cores, proceed running the Intel(R) Processor Identification Utility (Click here); this should confirm how the processor's running.
3. Ensure the BIOS is latest version. For this, please, check with Asus.