Nice to know. That would save me lots of time, not having to sand the heastsink to a perfect finish. I'll just wait a bit longer and re-apply with a different thermal paste for the final installation.
Yesterday I made a custom wire harness from the 4+4-pin CPU cable from the HD-Plex. Since the 160w power supply doesn't have a dedicated header for PEG I have to split it to make my own. The first 4 pins connect to power the CPU as usual. The other 4 pins have been modified to run cables for a 6-pin PEG connector. Two 12v cables, and three ground. Two of the grounds merge into one going back to the 4+4 header on the HD-Plex.
So how did it turn out?
It turned out pretty awesome, I would say. The HD-Plex is handling it like a champ. You may notice the larger power brick on the left side being used. I chose not to use the Dell 150w brick to test this time, but instead the whole system is using a HP 200w brick in order to cut my risks of overload on a system where I'm still going in blind with power consumption.
I ran some Valley and Fire Strike benchmarks and then played some Borderlands 2 for a while. No problems noticed so far. In GPU-heavy workloads, the performance is capped by the TDP limit, just as I want it. Cables are cool to the touch, and any heat is from usual sources (HD-Plex heatsink, graphics card and power brick)