the board of rtx4090 is actually small, the second back fan blows air from bottom up without any board in the way, the card is literally 40% longer just because of the heatsink + it is fat as hell, hard to imagine a bigger gpu. air cooling abilities are also maxed out, I dont think future cards can go over 500W in reference designs. rtx4090 is a true beast and I wish I could have it, but $1600 for a card just to play games is ridiculous now that gpu mining is dead. A year ago rtx4090 could mine over $5-6 per day, so you could theoretically mine its value back in 12-14 months depending on electricity prices,but today there is no way to recuperate the purchase price back. But if I ever have like $3000-5000 spare extra money, I might might finally build a water cooled rtx4090 maxine with 16-core ryzen, 64GB ram and 2x2tb gen4 nvme in raid0.