Interesting solution for those with throttling issues....

[blppt]

As some may know, for a while now, I've had problems with the cpu throttling back to 1404 under Prime95 testing, or h.265 encoding (heavy loads). The only way I was able to rectify this was either running the system with the water cooler outside the case, or lowering the voltage to 1.45V @ 5ghz. I previously figured this was because the VRMs were getting too hot with the LLC @ Ultra High, but when I noticed it throttling even after putting a fan blowing directly on the VRM heatsinks, I tried something else.

In the CPU settings page of the BIOS, I disabled APM and enabled High Performance Computing.

Voila. No more throttling. I cant believe this was the source of all my problems. Wish I hadnt just dropped $150 on a new Corsair 750D case in an effort to get better airflow over the Bitfenix Outlaw I had before. Although, the H110 I upgraded to wouldnt fit in that older case anyways, so thats nice.

Now, bear i mind you need to have APM enabled for Turbo to work, but since I'm running slightly oc'd @ 5ghz (all cores), I dont use TC anyways. And changing these two settings apparently does almost nothing to idle power draw, according to my UPS meter.

[blppt]

Its also worth noting that the jerky behavior I noticed when playing Dragon Age Inquisition with Mantle enabled also completely disappeared when changing those settings. Makes sense---Mantle is supposed to distribute the CPU rendering loads more evenly across more cores (obvious benefit to weak single-core AMD processors), so these two settings would make the cpu keep processor speeds even under high core loads. Direct3d always worked better for me in DAI until I changed these settings in the BIOS. Now Mantle works perfectly.

Just some interesting observations.

[AMD_FX_9370]

I went through the same dramas with throttling same stupid thing HPC is set to disable by default. http://rog.asus.com/forum/showthread.php?53285-Asus-crosshair-v-formula-z-with-fx-9370-can-t-stop-mu...

[Crayraven]

So should HPC be enabled if you OC?

[blppt]

Crayraven wrote:
So should HPC be enabled if you OC?

Granted, 5ghz on all cores is a very mild overclock, (or somewhat less than mild, depending on how you view the 9590 to begin with, it is, after all, basically a binned factory oc'd 8350). But yes, enabling HPC and disabling APM is what fixed my throttling issues for this *mild* 5ghz overclock.

[AMD_FX_9370]

"HPC Mode (High Performance Computing) - HPC Mode is a setting in the BIOS that prevents the CPU from lowering and locking its clock rate under load in certain conditions. In some benchmarks, HPC Mode can increase performance by about 6%, but these performance improvements are only realized in benchmarks like HPL. Dell tested this setting for the AMD Interlagos Server based CPU's and saw very little performance increase outside of HPL benchmarks. HPC Mode did however increase power consumption and power draw for very little benefit.

In a nutshell, HPC Mode prevents the CPU from locking and lowering its clock rate when the chip is either getting close to going over the TDP, or the motherboard CPU socket temp is getting to high. This is not always true in all cases though, because in certain situations, the CPU can still drop and lock its clock rate under load. This setting is more geared to very specific environments such as clustered computing where there are specific applications running that would benefit from this setting. Those situations are not your average home user."

[blppt]

I dont think there is anything *average* about the 220W 9590, LOL. Which may be why it actually does something for us home users with that chip.

[AMD_FX_9370]

Believe me i know first hand about the power draw of a FX9000 series chip. My previous board Asrock fatality 990fx killer with 8 phase vrm was getting insanely hot 130c on the mosfet heatsink under full load and putting out some noise. I sold it off as i knew it was going to die and bought the crosshair with a EK C5F-Z wb for peace of mind.