Issues with the i5-9400f processor performance
Issues with the i5-9400f processor performance
I'm just starting out with my i5-9400f. It has a boost clock listed as 4.1 GHz, which seems like single-core speed. But when I run Cinebench r20, none of the cores ever reach that number—they stay around 3.9 GHz or lower. I've used an aftermarket cooler and adjusted BIOS settings to lock the frequency at 4.1 GHz. I also increased the voltage, but nothing changed the boost behavior. Recently, I tried a BCLK overclock to see if it could help, but it didn’t affect performance beyond that point. When I cranked up the voltage, power consumption rose noticeably (from 40 to 60 watts), yet speed stayed the same. Where is the extra energy going?
For CPU frequency details, use CPU-Z version 2. Turbo settings include 4,100 MHz for single core, 4,000 MHz for two cores, 4,000 MHz for three cores, 4,000 MHz for four cores, 3,900 MHz for five cores, and 3,900 MHz for six cores—ensuring optimal performance.
Accept the details provided. Based on my observations, I believe Intel CPUs rarely reach their maximum single-core performance even when set to default levels. Probably only noticeable in Cinebench single-core tests, while actual applications tend to show limited gains beyond full cores.
In short, the "4.1 Ghz boost" claimed by Intel is primarily promotional rather than a concrete technical improvement.
AMD follows the same pattern. If you own a Z board and decide to tweak it, BCLK overclocking might give you a slight boost. I achieved around 4ghz on my 9400 (actually close to 3.98ghz). However, the jump from 3.8 to 4.1 is only about 200mhz—hard to notice.