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%.

- An Enthusiast-Oriented Pentium CPU?
- Overclocking Pentium G3258 And Athlon X4 750K
- How We Tested Intel’s Pentium G3258 And AMD’s Athlon X4 750K
- Results: Arma 3
- Results: Battlefield 4
- Results: Grid 2
- Results: Metro: Last Light
- Results: Thief
- Results: Tomb Raider
- Results: World of Warcraft
- Results: Synthetics
- Results: Content Creation
- Results: Adobe CC
- Results: Productivity And Media Encoding
- Results: Compression Apps
- Power Consumption And Efficiency
- Haswell, Unlocked, For £55

dont buy a pc so cheap you cant cool it or have a good motherboard.
When the i3 is £90 and can be put in a cheap (£40) H81 motherboard without needing the effort of finding a stable overclock it seems a bit risky to go for the Pentium.
However, if a later upgrade to an i5K or i7K is planned (or you need the Z series chipset features) then the Pentium is a good way to start saving towards that upgrade while not compromising on the expense of an i3 or drop in performance of a regular Pentium.
Zalman CNPS10X Performa(~35$) or
Thermalright True Spirit 120i(~45$) should be enough to keep it under 80 degrees.
SOURCE:http://www.tomshardware.com/news/asus-overclocking-h87-h97-b85,27076.html
Anything above 4.3Ghz wasn't stable, even with the voltage up to 1.34v (not prepared to try higher than that as temps were too high). This was likely down to the cheap mobo, but I'm not going to complain about that, as it's still a nice overclock for the money.