Testing only the turbo clock speed of an overclocked AMD FX CPU
Testing only the turbo clock speed of an overclocked AMD FX CPU
Lapping AMD CPUs and coolers is fine, but removing the case isn't required. Lids are attached directly to the chips, and some Intel models have this setup too. Removing the case only works for certain CPUs with poor thermal performance.
The lower TIM layer on Intel's CPUs is positioned between the core tops and the lid. All processors use TIM—whether it be thermal paste or solder—between the core units and the covers to facilitate heat transfer, which is beneficial rather than harmful. The problem arose because the TIM applied to these Intel chips was subpar and not optimized.
Taking off the lids doesn't always ensure a stable voltage drop during temperature changes. This issue became more noticeable with high-performance CPUs like the 8 GHz model, which is among the best in its class. For such advanced chips, only exceptional performance paired with liquid helium cooling could sustain the required speed without compromising stability.
Yep, that's what I thought too; I assumed TIM was thermal paste.
So you're saying those FX chips reaching 8 GHz @1.9V on LN2 are similar to those golden ones, but the most impressive ones are hitting 5.0 GHz @1.25V in air? That's insane! I didn't realize how much variation there is in the silicon lottery until I looked it up.
Also, should I aim for 5.0 GHz? I'm currently at 4.9 GHz @1.58125V with a temperature of 62°C.
TIM refers to any substance that aids in heat transfer. When the CPU reaches 62°C, it may begin throttling if frequency or voltage increases. I maintain a 10°C margin for temperature changes due to ambient conditions. It’s best not to push higher clock speeds without adequate cooling.
Well, you might consider turning on Turbo and raising the voltage a bit. With fewer active cores, your CPU would require less voltage at higher clocks. An FX 9590 operates at 1.53750V, 4.7 GHz with 8 cores, and 5.0 GHz with 4 cores. Safe SOI chip voltages typically hover around 1.55V. It seems you might have to settle for 4.9 GHz instead, as the extra cost of a custom loop and higher voltage isn’t worth it just for "5 GHz club membership". TBH, you could switch to the 1 Core per CU setting and use 3 cores, since each compute module shares two cores for the FPU and cache. Disabling one core per module can boost IPC slightly by about 10-15% and reduce temperatures, which in turn lets you use lower voltages or push overclocks further. Three cores offer a solid balance for dual-core games, with one core left for background tasks and music streaming.
I have turned on turbo core, but it won’t work unless APM is enabled, which forces the CPU to reduce all cores to 3.1 GHz during heavy use. This wasn’t the outcome I expected. Is there a method to enable Turbo core without APM active?
Because APM and turbo core are built for regular use, achieving this would be quite challenging. The issue with your CPU throttling in clocks stems from APM restricting the TDP to 95W no matter what the CPU voltage is. I recommend attempting a slight further overclock on your CPU to 4.8 GHz @1.5-1.525V and consider it a maximum continuous overclock. After that, move on to the RAM.
I have achieved stable performance at 4.838 GHz with a voltage of 1.572 volts, which I thoroughly tested before starting this discussion. However, any lower voltage leads to instability. As noted in my earlier post, the voltage is simply too high for my preferences, so I plan to use 4.739 GHz for continuous overclocking. My intention to enable the turbo core was to enhance single-threaded applications without requiring additional voltage, which aligns with my preference for maintaining performance above 1.5V on an FX CPU while still gaining more speed. This would mainly involve better cooling, which I already have in place.
Regarding the RAM, it tends not to overclock significantly. After testing, I found it unreliable at 2000 MHz across all voltages. I suspect the issue lies with the CPU itself. Even a modest increase of 118 MHz wouldn’t noticeably improve performance for the applications I use, since I’m already running at 1882 MHz without needing to boost voltage for memory or the memory controller. To raise the RAM speed, I’d need to lower my CPU’s core frequency to adjust the FSB/Base Clock, which would require some trade-offs.
I’m already pushing the RAM beyond its intended frequency, and I haven’t encountered any bottlenecks aside from the CPU’s inherent limitations. My AMD FX CPU is slower than my previous Phenom II 965BE in single-threaded tasks, especially on older games where the GPU becomes the limiting factor due to better per-core performance.
If I were concerned about my signature, I would opt for a 4.8, 4.9, or 5.0 GHz validation instead of relying solely on overclocking. While some users might benefit from an E-peen, I prefer to demonstrate my deep familiarity with these products by owning them myself. 😊
My current overclock is guided by AMD’s recommendations, which state the maximum voltage should be 1.5V. My chip operates at 1.476V under normal stress and 1.488V under full stress, and it even fluctuates during intensive tests like Prime95 and IBT. This suggests it’s not always necessary to push beyond that threshold, except occasionally.
I’m also aware that overclocking involves balancing temperature, voltage, and frequency. My system maintains temperatures between 12°C and 18°C under full load. A suitable balance should accommodate seasonal temperature shifts, adhere to manufacturer guidelines for maximum voltage, and allow for stable performance.
The decision not to exceed 1.5V stems from the fact that I didn’t purchase this chip new—it was third-hand but in good condition. The original owner had it in an HP H8-1234 system. I understand it throttled under stress, as evidenced by its behavior during tests. Here’s a link showing how severe the overheating issues were: [link].
My son, who is interested in IT, found this machine ideal for learning about hardware and maintenance. He ran it for over a year with an OC of 4.1 across all six cores using an H100i chip. I’m confident it wasn’t abused. After upgrading components—including a new case, GPU, motherboard, power supply, and AIO cooler—I purchased an FX 8320 for $20. Despite its age, it still shows signs of heat degradation, which explains the high voltage requirement.
I’m hesitant to replace this FX chip, especially with Ryzen on the horizon. I’d prefer to upgrade the CPU, motherboard, and switch to DDR4 RAM. Although it’s become more common to consider a new PC, my current system is still under warranty, and many parts are covered for another two years. This would allow me to benefit from Ryzen’s improvements and address existing issues before they become critical.
Same here, if I was aiming for E-Peen or bragging rights I would be using an unstable 5.0 GHz with 1.45V that only lasts about an hour.
"My CPU can run at 5 GHz at 1.45V stable lololol"
I believe you've reached a voltage limit. Your chip also requires significant voltage to reach 4.8+ GHz. The feeling that the voltage is too high or your chip is worn out comes from what you mentioned—some people might get E-peen from a signature, but they aren't stable at those levels. You might have gaming stability, but not Prime/F@H stability.
Heat buildup could be an issue, but keeping your CPU below 71.1°C (a very tight limit given the TJmax for FX-4/6 is 90°C) should keep you safe up to about 1.55V. Try it. With the right VRM and northbridge voltages, you might achieve 4.8~4.9 GHz at a lower voltage.
Even FX 9370s/9590s run smoothly at 1.51V all day. Don’t worry, you’re not alone.