One more thing: can I pull out the PCI-E (6-Pin) cable connected to Chain 4 while the Miner is runnning or do I risk damaging the hardware doing that?
When running I would no be messing with PCIe cables plugging in or out. I would do this with PSU off, as i you do when running your are unplugging and plugging in a live cable... so not the best idea.
The C1 is a little trouble to troubleshoot with the water it add's kinda a pain. What I tried on mine was repasting, I just did not have the time. But I sold as parts and I think after it was repasted 3 out of 4 blades worked. This is kinda last resort though I would try everything else before looking under and doing this. But if you do I suggest looking at amazon you can buy a small tub vs the standard syringe, and get much more paste.