Gear 1 can Lead to Performance Loss on Intel "Rocket Lake" 11th Gen Processors

In the course of our Core i5-11400F "Rocket Lake" processor review, we discovered that the Gear 2 memory mode has the potential to offer higher performance than Gear 1. The Gear 1 mode runs the memory frequency and memory controller frequency in 1:1 sync, while the Gear 2 mode runs them at 1:2, meaning that the memory controllers run at half the memory frequency, allowing you additional memory overclocking headroom. At lower, more stable, memory frequencies, it should be logical to use Gear 1. Our testing springs some surprising results.

Overall, a stock Core i5-11400F paired with DDR4-3733 MHz memory, was found to be 1.5% faster with Gear 2, when averaged across all our CPU tests, compared to Gear 1 at the same 3733 MHz frequency. Gear 2 was 3.42% faster in Cinebench R23 multi-threaded, and a staggering 6% in MySQL. Across rendering and media workloads that scale across all cores, we find Gear 2 faster by 1-3%. It's only with less parallelized workloads such as gaming, where we see Gear 2 lag behind Gear 1, though not by much. In our i5-11400F review, we show that by running your processor in Gear 2, you're making your memory controllers pull less power, freeing up power budget for the CPU cores, translating into the nT performance gains we see here. We discovered that the uncore can pull anywhere between 5 to 10 W more power in Gear 1 mode. This is valuable power eating into the already constrained power-budget of this 65 W TDP chip.

Read the Intel Core i5-11400F TechPowerUp Review

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