I know this is resurrecting a really old thread. But this really helped me to figure out how to get my FX 9590 to work in my computer. So I decided I would buy a captain 120EX AIO for my old FX 8350 which I've had for like 5 years. I needed a little more cooling because the factory heatsink was on the edge of barely keeping the cpu cooled below shutdown at 90C. Since I was just trying the water cooler setup and I had read that this is what is needed and so I figured I would try the FX 9590. I watched
which is from AMD and used the Captain 120. I bought the Captain 120 EX white which is nearly the same thing. I get everything installed with the FX 9590 and start my stress test. The stress test is compile Firefox, and rip a DVD to H.264 high profile quality level 10 in handbrake. This is an extreme workload which the old FX 8350 on stock cooler was running in the 80+ C range.
The Captain 120EX with ambient being 18 C ran the FX 8350 at 29 C idle and 56 C in the stress test. I was thinking at 20 C increase should handle the 100 watt increase. I was terribly wrong. So I tried a temporary duel fan setup on the FX 9590 and the cpu almost made it through the stress test, but hit thermal shutdown in the end of the compile of Firefox. I tried just straight underclocking to an FX 8350 speed and that did decrease power, but not enough to be safe. In the end the trick was to set the LLC to high and set the core voltage to 1.381 volts and the speed of the FX 9590 to 4.7GHz with boost to 5GHz.
Asus Sabertooth 990FX R2.0
Captain 120 EX white modified to be duel fan.
Cooler master HAF case with 2 fans in front intake, 1 side fan intake onto CPU area, and 1 top exhaust fan.
FX 9590 undervolt to 1.381V and factory speed 4.7GHz and 5.0 GHz turbo
motherboard setting of LLC of high
Stress test of Firefox 57.0.4 compile and handbrake DVD rip to H.264 high profile
Max temp 75C
Typical temp 70C
Low temp 65 C
Typical operating temps:
idle: 29 C
games: 55 C
internet browsing: 29C
Firefox only compile: 65C
Thanks for putting this info up online. Just a straight undervolt did not work. The trick is changing the LLC setting for the CPU.