This message was posted on behalf of Intel Corporation
In regard to your question, I looked for i7-6600, but that model is not showing in our web site, so it is probably model i7-6600u.
And yes, TAD is activated when SGX is enabled, 6th generation processors have SAD / TAD instructions enable; however, they are handled by Intel® Software Guard Extensions (Intel® SGX).
More details about them on the link below:
Intel SGX Explained:
Intel® Software Guard Extensions (Intel® SGX):
It is possible to enable or disable the option from BIOS of the board. Intel offers the feature but board manufacturers enable or disable the option by default on the BIOS.
On Intel NUCs, it is possible to enable it through Security tab.
Any questions, please let me know.