With the addition of numbers for the Intel Core i3-2100 and Core i5-2400 in some of our benchmarks, it's plain to see that even with a price cut, the FX-8120 struggles in most of our tests. In very multi-threaded tests such as Cinebench and WPrime, it just about manages to hold its own against the similarly-priced Intel Core i5-2400 - slightly ahead in WPrime, a little behind in Cinebench and noticeably faster than the cheaper Core i3-2100. The Core i5-3570K is much faster in both tests, but then it costs around £30 more.
Our image editing test was a real let down with the FX-8120. It came bottom of the graph, being trounced by a staggering 500 points by the Core i3-2100 - a CPU that costs just £90. Even the ageing AMD Phenom II X6 1100T Black Edition was considerably faster while the similarly priced Intel Core i5-2400 was nearly twice as fast. Clearly, if you do any amount of photo editing, the AMD FX-8120 represents particularly poor value.
With eight cores at its disposal, you'd think the FX-8120 might stand a good chance in our video encoding test. Sadly this wasn't to be and its score of 2,150 was over 400 points short of the Core i5-2400. Thankfully for the FX-8120, the Core i3-2100 was noticeably slower, with its two physical and two virtual cores not able to keep up.
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Everything started to fall away from the FX-8120 again in our multi-tasking test, where it was yet again at the bottom of the pile, coming 100 points short of the much cheaper Core i3-2100, while the Core i5-2400 was nearly 50% faster - pretty damning result. Overall, it was no surprise to see the FX-8120 rock bottom, bettered by the Phenom II X6 1100T Black Edition and Core i3-2100 and trounced by the Core i5-2400.
Our game test lacks data for the two Sandy Bridge CPUs as we tested these some time ago, however, with the Intel Core i5-3570K retailing for just £30-40 more, it's clear from our results that the FX-8120 isn't a great buy for games either. The Intel CPU was 60 per cent faster in Arma II while costing around 30 per cent more - not a bad rate of return if you can afford the extra layout.
As they're built for high frequencies, AMD's new CPUs are at least decent overclockers. By boosting the vcore to 1.4V, the Northbridge to 1.25V and with the memory at 1,600MHz, we used a multiplier of 23x to reach a frequency of 4.6GHz with an HTT of 200MHz. Raising the multiplier any further resulted in blue screens so we then tried bumping up the HTT as we did with the FX-8150 to stretch the frequency a little further. We only managed another 2MHz on the HTT to give a CPU frequency of 4.64GHz - a little way off the 4.8GHz we achieved with the FX-8150, but not a bad result from a 3.1GHz CPU either, although this significantly increased load power consumption.
This saw the FX-8120 do a little better in the benchmarks, nearing the Core i5-2500K in Cinebench and WPrime, and bettering the multiplier-locked Core i5-2400 in our video editing test by quite a long way. Sadly it still had dire performance in our image editing test where it was again beaten by a stock speed Core i3-2100, with the Core i5-2400 still a long way ahead in the multi-tasking test too. Overall, it managed to climb the graph at last, coming 40 points short of the 3.1GHz Core i5-2400. In Arma II, the 6fps boost to the minimum frame rate saw it climb a little way up our graph, but it was still slower than the AMD Phenom II X6 1100T Black Edition, while the Core i5-3570K was in a different league.
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Sadly, its more of the same bad news for AMD or anyone with a Socket AM3+ motherboard looking for a decent CPU for around the £150 mark. The FX-8120 just isn't a good choice when it comes to the kind of applications we run on our PCs. It's regularly outpaced by far cheaper Intel dual-core CPUs, while the similarly-priced Intel Core i5-2400 is significantly faster in many of our tests. It's not all bad news for AMD - before we get accused of being biased towards Intel, we have no qualms recommending the A8-3870K for those looking to build a budget gaming PC, while we also recommend many of its graphics cards.
As it stands, the FX-8120 will have to be a lot cheaper for it to be worth considering over an equivalently-priced Intel setup, while owners of the Phenom II X6 1100T Black Edition can rest assured that there aren't any worthwhile upgrades yet.