We've seen a few revisions of the 'FlowFX' cooling solution since the first previews of GeForce FX 5800 Ultra's were made available, and judging by the clear plastic ducting this would appear to be the later revision. This revision is supposed to run quieter in 3D mode than the previous versions, yet the fan noise is still quite loud and can be heard over my other PC's Lian-Li case, with 4 system fans and a CPU fan. This version does spin down entirely in 2D modes (which runs at 300/300), which means the board is passively cooled, and completely silent. During testing the fan did spin down quite frequently, presumably because the board was overheating, when running 3D applications, also reducing its 3D performance.