The 3 packs come with 1x 600mm Cable with straight-90 connectors, the Single fans come with 1x 135mm Cable with 90-90 Connectors. Assuming you'll install the single on the rear, 3 at top and 3 at front or side, You'll connect the single to the top 3 with the 135mm cable, the top 3 to a port on the link-hub with the 600mm, the other 3 connect to the other port of the hub with the other 600mm. You'll need an available USB header to connect the hub and a PCIe 6+2 power cable. More on reddit.com

More LEDs on LX really. https://imgur.com/a/lMcmsZ6 Performance is similar. More on reddit.com

See here: In short ... QX are the prettiest with pretty good performance. They also have temp sensors (not listed). LX are almost as pretty as the QX and has the highest static pressure. No temp sensor. RX have the best CFM and are the least pretty. They have lower static pressure than the LX but that may be due to the lower fan speeds. QX and RX both support "Time Warp", which I think is pretty cool. It flashes the LEDs at high speed so it looks like the fans are 'still'. I'm sure that there are those that hate it and those that, like me, like it (I use it for my hardware mode). All of them will perform well in any use case, though one may be a bit better for a specific use case than the others. you can certainly mix and match them on the same iCUE channel - that's not a problem at all. You'll configure each type separately in iCUE. More on reddit.com

QX series remain prettier for my eyes, even when their back is shown :) More on reddit.com