Conclusion: Core Efficiency Beats Core Count
Having watched the Pentium G3258 and Athlon X4 860K trade blows in no less than 20 games using two mid-range GPUs, the G3258 is undeniably faster and it's the processor you want if you're building our Budget Box with the intentions of gaming.
This might surprise a few of you given that the Athlon X4 860K is a quad-core chip clocked up to 4.0GHz, while the Pentium G3258 is a lowly dual-core that runs at 3.2GHz out of the box.
The problem for AMD, which we have seen time and time again, is core efficiency. Having more cores available isn't much use if they are slower. Moreover, just because a game can use four cores (and all the games we tested could) doesn't mean a dual-core will be inferior if two cores are working harder than four.
Most of the games saw the Athlon X4 860K working all four cores at 70% capacity or greater, with a few such as Civilization: Beyond Earth, Thief, Battlefield Hardline and Battlefield 4 reaching 90%. Despite that, in all of those games the Pentium G3258 was as fast or faster than the Athlon X4 860K.
Focusing on the overclocked 4.4GHz results we found that on average the Pentium G3258 was 15% faster than the Athlon X4 860K when paired with the Radeon R9 285 and 14% faster with the GeForce GTX 960.
If we remove Assassin's Creed Unity results, which saw the Athlon X4 860K deliver abnormally low results, the G3258 was still 13% faster with the R9 285 and 9% faster with the GTX 960.
Looking at the GTX 960 data, as this seems to be best case for the Athlon X4 860K (with the Assassin's Creed Unity results removed), we find on average 4fps favoring the Pentium G3258. That's not a huge amount, but every last frame counts in games such as The Witcher 3: Wild Hunt, Total War Attila, Dying Light, Arma 3, Metro Redux and Crysis 3 for example where the average frame rate was 40fps or lower.
For a lot of the games, such as Tomb Raider, Sleeping Dogs, Battlefield Hardline, Watch_Dogs, Hitman: Absolution and Dragon Age: Inquisition, performance was so close it really didn't matter, so you could happily go either way. Sadly though, the Athlon just doesn't deliver the same consistency as the Pentium G3258, being much slower at times.
At this point you may have noticed we decided to skip the power consumption testing. We didn't see the need to dredge up those results for this type of article, we all know Intel is much more efficient here based on results from previous articles.
Finally, aside from performance, the Pentium G3258 and its LGA1150 platform offers some other advantages over the FM2+ Athlon X4 860K. Upgradability is a key feature here, as gamers have the option to drop in a Core i3, i5 or even i7 processor down the track.
Touching on that a little more, the Core i3 isn't really an ideal upgrade. Although it does support four threads thanks to Hyper-Threading, the highest clocked model runs at just 3.8GHz with no Turbo boost, so it won't be much of an upgrade from an overclocked G3258, if at all.
The Core i7 makes little sense for gaming if you care about value so this leaves the Core i5 range and for LGA1150 users there are plenty of options, from the $185 Core i5-4430 to the $240 fully unlocked Core i5-4690K.