Okay, added 2 92mm fans onto the 5v rail of PSU2 - had to help them start turning but they kept going on their own after than
Just let it boot into Gamers OC which I had set last night and it booted up on the first attempt. Nothing earth shattering at ~4700mhz, but better than it would do yesterday. Shitty RAM timings too on this one... default gamer oc I guess? Set the cards up to 845 and ran a vantage test (this time with with the CPU handling the Physx)
Hard to get a good screeny cause in this mode effing Speettrap is still on so it bounces from 1200 up to 4700. Caught it the fastest I could but forgot to drop down the box to show the 4 GPUs.
Next test will be full extreme oc, and we'll see what happens. May still need to balance the load between the PSUs better