FX-8320 with 990FX experiencing throttling problems
FX-8320 with 990FX experiencing throttling problems
My 8320 is running on an ASRock Fatal1ty 990FX Killer with a Phanteks PH-TC14PE cooler. This is my first attempt at overclocking, and I've reviewed all the documentation. In the BIOS, I turned off APM, C1E, C6, Cool 'n' Quiet, AMD Turbo Core, etc., but when using Prime95 for stress testing, the system throttles—multiplying down from 22.5 to 7, dropping from 4500 MHz to 1400 MHz every few seconds. Once it begins, it alternates between those two speeds. Monitoring temperatures via HWMonitor and AMD Overdrive suggests it stabilizes after thermal equilibrium, typically around 50-53°C (a 20-17 degree margin according to Overdrive), so temperature-wise there’s no major concern.
I’m just beginning the overclock process, so I’ve experimented with various voltages and found consistent results. Currently, I’m at Vcore = 1.400. The latest BIOS version is installed. Any additional details would be useful for troubleshooting?
Thanks for the assistance.
Which power supply do you have? Three factors lead to throttling, overheating, unstable power, and a bad CPU. Overheating isn’t the problem here; only two options remain. Either your PSU can’t provide a steady power supply (possibly due to VRM or phase regulator issues in the motherboard, though your board is reliable in that regard), or you have a low-quality CPU which sometimes behaves this way. To determine the cause, use HWMonitor Pro to check voltages during stress tests—if the voltage drops significantly, the PSU is likely the issue.
CPU-Z displays the voltage drop when the frequency is high, but I'm struggling to understand if it's the PSU causing the issue. With my EVGA 750 G2 at half load maximum, it might be CPU binning, but I need to try other possibilities before giving up. Should I be able to run stably at turbo frequency? Please let me know what else I can do. Thanks, by the way.
The situation seemed to resemble an APM issue or another throttling mechanism that wasn’t turned off. After further investigation, I discovered this discussion:
http://forums.tweaktown.com/asrock/46817...t-apm.html
This matches my own experience. I applied the fixes in the previous two posts on the thread—changing the tuning profile and adjusting fan speed didn’t resolve it, but the final attempt worked. I then needed another tool to set the p-states correctly, which allowed it to run. Stability problems remain, but it’s a workaround.
It appears the issue might be related to Cool 'n' Quiet, which I had disabled in BIOS. Anyone know why the BIOS settings didn’t take?
The situation seemed to resemble an APM issue or another throttling mechanism that wasn't actually turned off. After further investigation, I discovered this relevant thread: http://forums.tweaktown.com/asrock/46817...t-apm.html. This matches exactly what I'm experiencing. I attempted solutions in the previous two posts on the thread—changing settings to F-stream tuning power profile and adjusting fan speed, but neither resolved the problem. The final attempt required using another tool to set all p-states to the desired multiplier/voltage, after which the system started working again. Stability issues remain, but it's a workaround. It appears the issue might be related to Cool 'n' Quiet, which I have already disabled in BIOS. Anyone know why the BIOS settings didn't take? Do you use AMDMSRTWEAKER to modify p-states? Is there a specific command to disable Cool n Quiet? If you can walk through your steps, I hope it helps me get my OC stable. Thanks!
I rely on AMDMSRTweaker as described in this guide. The process aligns closely with the undervolting method but functions similarly for overclocking. Occasionally, I discover that unless I first configure it in AMD Overdrive and then apply AMDMSRTweaker, the settings remain unchanged. The recommended approach is to adjust BIOS settings, verify them in Windows, and finally use the tool to standardize all p-states.
I face the same problem with my 990FX Killer, whenever I exceed 1.4V it reduces its speed to a factor of 7. I think the issue might be with the VRMs on the board since the heatsink gets very hot. I've brought the top 120mm fan nearer to the VRMs and added a 70mm fan from the standard cooler to draw air from them. It has made a small difference but not much.
I experienced the same issue with my CPU, where reading around causes significant throttling if you exceed the specified speed. Turbo Core showed less throttling compared to a 4400 MHz overclock. Using a high-end cooler greatly reduced throttling from the stock fan. If you choose to follow the recommended maximum overclock, set your multiplier to 20.0 instead of relying on Turbo Core.