As the OP.. here goes
After playing COD MW recently, my temps were peaking again and I got fed up.
1070ti on a 120 aio (custom bodge mount
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and the 9700k on a 240 aio oc'd to 4.8
GPU was hitting 75 and the CPU was hovering at 70 odd..
So I removed all the cooling and fans, cleaned out, and discovered my MOLEX TO 3 PIN PUMP POWER was 5v (red) not 12v (yellow)
FFS
So as I was using a fan splitter, it was limiting the pump speed for both the GPU and CPU aio's.
I've tried using the AIO header on the board and didnt find it helped much (the speed kept changing) and I like my pumps to stay at 100%.
Now it's using 12v, reseated both aio's with some new Noctua fans and it's running like an absolute dream.
Also I HIGHLY recommend using Argus Monitor for Fan control (30 day free trial) and it's only £7 for 2 computer license. (no i'm not an employee just loving it!)
I'm using mobo headers to run the fans on the GPU aio so Argus allows me to monitor the gpu temp for those fans, stuff like that.
Now Prime95 hits max 72 on smallffts, 62 on mixed.
GPU maxes out at 55 in MW.. and it's super super silent.
So much happier.. yay!
Merry Christmas All!