I think i figured it out. For some reference, I have a 3090 and I use CableMod extentions. I did not realize that for high end cards like the 3090 and 4090, you must use 2 different PCI-E cables instead of using the PCI-E pigtail and connecting the GPU on one PCI-E cable. Once I used 2 seperate 8 pin PCi-E cables, Unreal Engine stop freezing on me. I hope this helps