My biggest question in all this is they use these super high end systems and then use a 60hz monitor. I wonder how different these results would look with a 120hz refresh rate when they do v sync tests.
You could try a higher Db gain antenna.
Increase signal strength maybe stop some of the dropouts.
Going wired would be your best option imo. I used to have a router that would drop out when the microwave was in use.
You can try loading up maybe only one or two of the cores while stress testing as opposed to all of the cores and see what the voltage reads. As you load more cores the voltage may drop slightly, this is VDroop. When something starts to draw more amperage from its power source under a heavy load or goes from idle to load very quickly the voltage can start to drop slightly.
In the bios have you made sure all cool and quiet options are turned off and the cooler motor/cpu fan header are running at full RPM? You could even use speed fan to make sure it's turned up all the way.
Could be a bad mount. Have you ever redone the thermal paste between the cooler and the CPU?
Also if you can redo that bundle of wires and move it under the front of the Video card it may help.
Also this connector looks like it is for I'm guessing the front fan. Try plugging it in to one of those fan plugs.
If you can take a sharp pair of cutters or a razor knife and snip the sides of those connectors out they will be fine, just make sure the notches line up.
Also does the front fan on that case work? I see what looks like the fan connector in one of those pics.
And if you can clean up those wires in front of the GPU, they are blocking most of the airflow from the front.