I think this was 78% of gross revenue. As OP stated, the GN video makes it clear that the margin on this was, in many cases, negative.
No - the margin is in many cases negative, right now, with high-end GPUs 50% below MSRP. This is an important distinction.
Margins were great for 2 years, EVGA's GPU department made tons of money during that time even with a few gestures towards the public. He lost tons of money during those years with frivolous, high-R&D, high-ongoing-support-cost ventures like entering the motherboard and enthusiast monitor market.