Surprisingly we still get asked quite often from gamers which kind of processor they should purchase for their next upgrade. As a general question there is nothing surprising about this and as a hardware site we are always trying to help gamers and PC users with buying decisions. However we are more surprised by the fact that many are still concerned that now might not be the best time to upgrade to a quad-core processor or greater.

Of course the cause for concern comes down to price for many and when looking at the Intel lineup for example, their cheapest current generation quad-core processor is the Core i5 750. While many including myself view this processor as a bargain at $200 US, that is still quite a bit of money, especially when the dual-core equivalent can be had for almost half that price.

Making the transition to a quad-core configuration a little more realistic is AMD with their current range of Phenom II X4 and Athlon II X4 processors, some of which cost less than $100 US, while the most expensive is priced at just $180 US. These processors offer gamers a tremendous amount of value and are the best option for those on a tight budget.

Those not as restricted by their budget will no doubt be interested in a Core i7 quad-core processor, and with the cheapest model priced at around $300 US, they are intended for power users that are not going to question how many cores today’s games need.

In the past we have often tested new and exciting games using a range of graphics cards to try and give gamers an idea of what, if any, upgrades they might need to make to their current gaming system in order to enjoy that particular title in all of its glory. Such articles also often include processor scaling results that feature a number of different processors.

Furthermore, we would also disable cores on the more powerful processors, such as the Core i7, to see what kind of impact this had on performance. Based on our experience, powerful processors such as the Core i7 cannot always be used to measure dual-core performance by disabling two cores. This is because they will still closely match cheaper quad-core processors in terms of performance and as a result are considerably more powerful than any dual-core processor.

Therefore today we hope to take a more accurate look at the impact extra cores are having on games. While we are sampling just short of a dozen games, we feel the lineup should give you a good idea of what can be expected from most games.

The AMD Phenom II X4 965 saw a 13% decrease in the average frame rate when disabling two of the four cores. Performance dropped by 71fps to just 62fps when testing with Battlefield Bad Company 2, while the minimum frame rate also dropped by 19%. Then, when disabling another core, turning the Phenom II X4 965 into a single core 3.4GHz processor, performance was slashed by another 40% with the average frame rate reaching just 37fps.

The Intel Core 2 Quad Q6600 processor saw an even greater reduction in performance when going from four cores to just two. The dual-core configuration was 23% slower when testing with Battlefield Bad Company 2 when measuring average frame rate performance, while the minimum frame rate was 26% lower. Finally, when going from two cores to just one, the performance plummeted by 47% to an average of just 28fps, while the minimum frame rate of 20fps was less than half that of the dual-core configuration.

Interestingly when testing with the Intel Core i7 920 processor we only saw a 3% reduction in the average frame rate when going from four cores to just two cores. Even the minimum frame rate was only reduced by a 7% margin, dropping from 58fps to 54fps. The Core i7 920 did suffer with just one core as the average performance dropped to 41fps, making it 39% slower than the dual-core configuration.

Similar margins were seen when testing with the Core i5 750 processor when compared to the Core i7 920, please remember the 920 does have Hyper-Threading disabled. Again the dual-core and quad-core configurations delivered similar performance, while the Core i5 750 really only suffers in Battlefield Bad Company 2 with just one active core.

Far Cry 2 is thread optimized and as a result we see a 27% performance decrease on the Phenom II X4 965 when going from four cores to just two. Then, when going from two cores to just a single core, performance is reduced by a 42% margin with the average frame rate dropping from 33fps to just 19fps.

The Core 2 Quad Q6600 saw a similar performance loss, as the 42fps seen with all four cores enabled was reduced by a 36% performance margin, to just 27fps with two cores enabled. Finally the single core configuration was 48% slower when compared to the Core 2 Quad Q6600 working with two cores enabled.

This time the Core i7 920 did become considerably slower with the 3rd and 4th cores disabled, as the dual-core configuration was 40% slower with an average of just 37fps. Performance was then decreased by another 46% margin when going from two cores to just a single core.

The performance margins where again much the same for the Core i5 750 processor as they were for the Core i7 920 processor.

Crysis Warhead, and games like it, that are entirely GPU dependent will not show any performance advantages when working with multi-core processors. The Phenom II X4 965 delivered much the same performance with a single core as it did with four in this particular game.

The Core 2 Quad Q6600 showed the same level of performance when working with two cores as it did with four cores. However the single-core configuration did provide a 15% reduction in the average frame rate which was not seen with the Phenom II X4 965 processor.

Unsurprisingly the Core i7 920 processor delivered much the same performance in Crysis Warhead with one cores as it did four.

Like the Core i7 920 processor the Core i5 750 also delivered similar performance with one or four cores.

Call of Duty Modern Warfare 2 looks to be another game that works just as well on a dual-core as a similarly powerful quad-core processor. With two or four cores active the Phenom II X4 965 averaged 61fps, while the frame rate did drop to 52fps with a single core, which was a 15% performance reduction.

The Core 2 Quad Q6600 also saw no difference in performance when going from four cores to just two cores. However this time the single core configuration was 32% slower than the dual-core setup.

The Core i7 920 was almost as fast with just one core enabled as it was with two or four cores when testing with Call of Duty Modern Warfare 2.

Like the Core i7 920 processor, the Core i5 750 saw almost no performance lost when going from a quad or dual configuration to just a single active core. In fact the average frame rate dropped by just a 7% margin when going from two cores to just a single core.

Just Cause 2 is another game that does not appear to be very CPU friendly, using just a single core with the Phenom II X4 965 processor.

Interestingly where as the Phenom II X4 965 appeared only to use a single core, the Core 2 Quad Q6600 was found to be 17% slower when only using a single core, opposed to two. However there was no difference in performance when going from two cores to four.

The Core i7 920 results are interesting as the dual-core and quad-core average frame rates are much higher than those seen when testing with the Phenom II X4 965 or Core 2 Quad Q6600 processors. There was also a 17% reduction in the average frame rate when going from two cores to just a single core.

Once again similar margins were seen when testing with the Core i5 750 processor. That said, this time the dual and single core results were quite similar, while it was the quad-core result that raced ahead.

Many have slammed S.T.A.L.K.E.R.: Call of Pripyat for being a poorly coded game, and as you can see there are no processor optimizations. The Phenom II X4 965 was just as fast with a single core active as it was with all four cores working.

Even the Core 2 Quad Q6600 only saw a slight performance decrease when going from four cores to just one, with the performance dropping by an 11% margin.

We were not surprised to find that the mighty Core i7 920 processor delivered similar results to that of the Phenom II X4 965, meaning that there was no difference in performance when enabling/disabling cores.

The Core i5 750 processor also showed no difference in performance when testing with S.T.A.L.K.E.R.: Call of Pripyat.

Metro 2033 is another game that has been slammed for being very poorly coded, despite the fact that it is a very visually impressive looking game. As you can see, the processor does little to help performance in this game, with the average frame rate locked at 21fps despite the number of cores active.

The situation is the same with the Core 2 Quad Q6600, which delivered much the same performance with just one core enabled as it did four.

The Core i7 920 was also able to deliver much the same performance with a single core as it was four.

Finally, no surprises here, as the Core i5 750 provided the same performance with a single core enabled as it did four when testing with Metro 2033.

Supreme Commander 2 only saw an 8% reduction in average frame rate when going from four cores on the Phenom II X4 965 to just two cores. That being said, the minimum frame rate did plummet by a 24% margin from 33fps to just 25fps. The single-core configuration was unable to play Supreme Commander 2 in our test, with an average of just 11fps and a minimum of 3fps.

The Core 2 Quad Q6600 was 10% slower when using just two cores opposed to four when test with Supreme Commander 2 when measuring average frame rates. However it was again the minimum frame rate that took the biggest hit, dropping by a 26% performance margin.

Even the Core i7 920 processor saw a 14% reduction in the average frame rate when going from four cores to just two cores. The minimum frame rate also fell by a 21% margin from 33fps to just 26fps. The Core i7 920 was also unable to deliver playable performance with just a single core enabled.

Finally the Core i5 750 dropped from an average of 56fps to just 47fps, as performance was reduced by a 16% margin. Again this proves that Supreme Commander 2 does require a quad-core processor for maximum performance.

When testing Splinter Cell Conviction with the Phenom II X4 965 processor we find that the quad-core and dual-core configurations both averaged 54fps with a minimum of 26fps. It was only until we enabled just a single core that performance dropped off, with the average frame rate falling by a 26% margin.

The Core 2 Quad Q6600 did see a minor reduction in performance when going from four cores to just two cores, around 8% performance was lost. However when going from two cores to just a single active core, performance did fall by a 36% performance margin.

Again we only see an 8% reduction in performance when going from a quad-core configuration to a dual-core configuration, this time when testing with the Core i7 920 processor.

The Core i5 750 displayed similar performance to that of the Core i7 920 processor, as we have seen time and time again. While the difference in performance between the two core and four core configurations is minor, it does seem like Splinter Cell Conviction does play best with a quad-core processor.

Mass Effect 2 is clearly optimized for quad-core processors, as we found when testing with the Phenom II X4 965. Performance dropped by a staggering 28% when going from four cores to just two cores, while disabling another core reduced performance by 24% again.

Similar performance margins were seen when testing with the Core 2 Quad Q6600 processor. The dual-core configuration was 25% slower when compared to having all four cores active. However a massive 39% reduction in performance was seen when going from two cores to just a single active core.

The performance hit was not quite as great on the Core i7 920 processor, though it did still suffer a 23% performance reduction when going from four cores to just two cores.

Finally the Core i5 750 processor dropped 27% of its original quad-core performance when working as a dual-core processor. Clearly Mass Effect 2 is a game that plays best on a quad-core processor.

Finally we have World in Conflict and here the Phenom II X4 965 was just 8% slower with two cores enabled, compared to the full four cores. Going from two cores to just a single core reduced performance by a 45% performance margin, as average frame rates dropped from 44fps to just 24fps.

The Core 2 Quad Q6600 was 12% slower when working with just two cores, opposed to four cores. Then, when going from two cores to just a single working core, performance was reduced from 38fps to just 16fps, a 58% performance reduction.

The Core i7 920 did not suffer much in the way of a performance loss when measuring the average frame rate performance between the dual and quad-core configurations. However if you look at the minimum frame rate, the Core i7 920 became 28% slower with just two cores enabled, opposed to four cores.

Finally, while the average frame rate performance dropped by a 10% margin when going from four cores to just two cores, the minimum frame rate fell by a 35% margin.

The biggest issue we found when playing games that could properly utilize four cores was that a considerable amount of performance was lost when using a dual-core processor. Take the Core 2 Duo vs. Core 2 Quad debate for a moment.

When comparing equally clocked processors the Core 2 Duo was on average 19% slower when testing with Battlefield Bad Company 2, Far Cry 2, Supreme Commander 2, Splinter Cell Conviction, Mass Effect 2 and World in Conflict. Furthermore, the minimum frame rate was 23% lower, which is a massive difference for the processor to make and will certainly be noticed in-game.

However in the half a dozen mentioned games, the Core i7 920 was also on average 16% slower, while the minimum frame rate was 22% lower. So even a powerful processor such as the Core i7 920 still struggles in these games without the correct number of cores.

If we were to only test in games such as Crysis Warhead, Call of Duty Modern Warfare 2, Just Cause 2, S.T.A.L.K.E.R.: Call of Pripyat and Metro 2033, then we would conclude that for now gamers still only require a dual-core processor. Overall these games only saw an average frame rate reduction of about 1% when going from four cores to just two cores.

As newer game engines are developed we are confident that games will become better optimized for quad-core processors and before long they will become compulsory for gamers. For those wanting to know if hexa-core processors are necessary for gaming, we already know from our Phenom II X6 1090T and Core i7 980X reviews that they are not and provide no tangible performance gains over similar quad-core processors.