Overclocking Pentium G3258 And Athlon X4 750K
In the past, I could have given you a play-by-play of how a low-cost processor comparison would go, without even touching hardware. The stock AMD CPU would have likely been beaten by Intel’s more efficient architecture, but then we would have overclocked to see AMD step into a more commanding position. Now, with both processors tunable, it’s anyone’s game.
Overclocking Athlon X4 750K
Let’s start with a known quantity. The Athlon X4 750K starts life as a Trinity APU, manufactured on a 32 nm process. Its CPU complex is Piledriver-based. To that end, it features a pair of modules, each with two integer units and a shared floating-point unit. AMD calls this four cores. The company then disables the graphics component of the APU, yielding a pure host processor with no Radeon engine to consume thermal headroom. And yet, the Athlon retains a 100 W TDP rating.
By default, the 750K sports a 3.4 GHz base clock and a 4 GHz maximum Turbo Core frequency. There’s a 3.7 GHz boost state in between, too.
Using MSI’s FM2-A85XA-G65 motherboard, we were able to increase voltage to 1.5 V and get all four cores running at 4.5 GHz through much of our benchmark suite (with a 2.2 GHz northbridge). Unfortunately, random crashes nudged us down to 4.4 and then to 4.3 GHz for total stability in Prime95. Temperature wasn’t the problem. AMD’s OverDrive software reported more than 25 degrees of margin throughout. And we simply didn’t want to push any higher on the voltage.
After slowing to 4.3 GHz, we were able to pull back to 1.425 V for a more comfortable long-term setup.
Overclocking Pentium G3258
With no precedent established, we borrow principles from our Haswell-based K-series CPUs for tuning the Pentium G3258 on MSI’s Z97 Gaming 7 motherboard. An unlocked multiplier makes it easy to test the chip’s upper bound. Given a fairly aggressive voltage on the Athlon X4, we went ahead and used 1.3 V to get Intel’s contender running at 4.7 GHz with both cores taxed and 4.8 GHz in single-threaded workloads. Despite temperatures in the mid-60 °C range, though, that proved unstable through our entire suite.
Eventually, we settled on 4.5 GHz with two active cores and a maximum Turbo Boost setting of 4.6 GHz for unflagging stability under Prime95. That sounds fairly modest for something like a Core i7-4770K. But remember this is a 3.2 GHz CPU overclocked more than 40%.
