That’s exactly what Reddit user zaME19 did on the r/sffpc subreddit, a subreddit for small form factor PCs. He built his own housing using a 3D printer, into which he installed three Noctua NF-A9 PWM fans. This allowed him to build the Inno3D GeForce RTX 4090 into his compact small form factor PC.
The GeForce RTX 4090 Selfmade Noctua Edition – source: reddit user zaME19
The problem was that the card got too hot and noisy to be useful in an SFF build. Reddit user zaME19 has therefore disassembled the Inno card but used Inno’s existing cooling solution. However, he has installed quieter and better fans, namely the Noctua NF-A9 PWM fans with a diameter of 92 mm.
With this solution the card is a lot quieter and on average 8 degrees cooler than with Inno3D’s standard cooling solution. He can now use the card properly in his SFF PC case. However, the question is whether this is good for your warranty and whether you dare to do this yourself with such an expensive video card. But this Reddit user can be proud of himself for building the first GeForce RTX 4090 Selfmade Noctua Edition. If you want to know more, visit his subreddit as well.