Please remember that any mention of competitors, hinting at competitors or offering to provide details of competitors will result in an account suspension. The full rules can be found under the 'Terms and Rules' link in the bottom right corner of your screen. Just don't mention competitors in any way, shape or form and you'll be OK.
You use the 6pin on any current Nvidia card and 2x 6pins on a Ultra (not sure on GTX)
You need 2x 6pins on the GTX
Otherwise a it will complain.. with lots of noise!