So...with Ryzen coming out, I'm seeing a lot of misinformation about CPUs with lots of cores and how they're not worth it for gaming. The common knowledge I'm seeing from some is that a quad is all you need, and games may not use or need more cores within the lifespan of the CPU. I'm going to prove here that this is demonstrably false as benchmarks prove that games do use more cores and that it might be a good idea if you plan to upgrade to Ryzen to go for a model with more cores than just 4. This isn't to say that 4 won't do well for the time being, but given future trends in CPU core usage, we might see CPUs using 8 cores regularly within a few years, just like we saw quads become standard over the last 7 years or so.
So, let's discuss why this idea that quad cores is the gold standard exist. Before Ryzen comes out, quad are standard because of the products on the market. There are CPUs with more cores, but they're either very weak (AMD's FX series) and don't perform as well consistently as a stronger quad like an i5, or they're prohibitively expensive like intel's i7 line. However, with AMD Ryzen coming out and pushing 8 cores for the price of an i7, and 6 cores for the price of an i5, arguably with comparable or slightly inferior IPC to intel's lineup, we might see a scenario where it will finally be worth it to buy a CPU that has more cores.
So, let's look at some benchmarks. I'm going to compare the FX line to each other, and the i5s to the i7s for reference points for how well multithreading works. I'll be focusing on games that primarily use more threads...obviously not all will, and quads will do for many games today still, but I do want to show how you might see a performance boost with more cores.
Battlefield 1
BF1 is probably the best example of a game that uses more cores, and as we know, when EA pushes CPU tech with their battlefield series, that will often become a precedent for future games to follow.
So, we have an FX 4300 CPU doing 57 FPS with 49 average, a FX 6300 doing 78/65, and a FX 8350 doing 92/77.
There are some clock differences, but say performance scales perfectly with clock speed and we put all of these at 3.5 GHz to compare.
That means that the quad core does 52.5, the 6 core does 65, and the 8 core does 80.5.
That's a pretty big boost in performance. The 6 core CPU does 24% better than the quad, and the 8 core does 24% than the 6 core, and 53% better than the quad core. Note that the 8350 still does worse than the i5 2500k in minimum FPS. This is why quads are still the gold standard. AMD's IPC is so weak with the FX CPUs that 8 cores still can't match a quad. But that doesn't mean the game can't properly utilize 8 cores if they exist.
Let's look at intel now.
2500k gets 88 FPS, 2600k gets 115. Hyperthreading has the effect of adding 26% to the performance here controlling for clock speed.
With the 4000 series, we get similar results. The 4770k is 26% faster than the 4670k.
6000 series, same story. i7 is 26% faster than the i5.
And if we look at the i7 5960x, despite being lower clocked, it's on par with the 6700 (although this might be due to a frame cap) and it beats out 4770k. If we clocked the 4770k down to 3 GHz, we'd see a 30% improvement over the 4770k.
So, it seems quite clear both multithreading and more cores do add performance. It might not scale perfectly. Going from 4-6 cores should improve performance by 33%, and 6-8 should yield 25%, but more cores are used, and you do get more performance. Hyperthreading itself seems to yield a good 26% more performance. It doesn't seem as effective as more physical cores is looking at how i3s perform against i5s, but it does seem to add performance.
Overwatch
In Overwatch, controlling for CPU speed and once again assuming perfect scaling per clock, we see the FX 6300 perform 33% better than the 4300. We see the 8350 perform 8% better than the 6300 and 44% better than the 4300. We see a huge jump going from 4 cores to 6 cores. The difference between 8 and 6 though seems to be dominated more by a higher clock speed (if we knock the 8350 down by 12.5% we get 123 FPS to the 6300's 114).
Looking at the effect of hyperthreading is harder in this game because of the 144 cap, so I won't vother doing it. It should be noted only the i7s and the FX 9590 seem to get a consistent 144 FPS though so those extra threads are doing something.
Battlefront
Another EA game based on frostbite.
Here the 6300 controlling for clock speed performs 19% better than the 4300 and the 8350 does 18% better than the 6300 and 40% better than the 4300.
Not as good as BF1, but still significant. EA's clearly been improving the multithreading of its engine.
The difference between the 2500k and 2600k is about 18%. 4670k to 4770k is about 15%. And the i5 5960X, despite being slower, is faster than all of them. if we knocked the 4770k's clock speed down to 3 GHz, the 5960x would be 23% better.
Fallout 4
Controlling for clock speed, FX 6300 is 10% faster than the 4300. 8350 is 9% faster than the 6300, and 20% faster than the 4300.
Hyperthreading on the intel side seems to have a MUCH larger effect.
2500k to 2600k is 17% faster. 4670k to 4770k is 13% faster. And once again, the best CPU seems to be the 5960x with 8c/16t, despite its low clocks.
This isn't to say that in this case that there isn't diminishing returns here. But games are benefitting from increased cores.
Grand Theft Auto V
In GTA V, once again, controlling for clock speed, the 6300 performs 19% better than the 4300. The 8350 performs 6% better than the 6300 and 26% better than the 4300.
The 2600k performs 13% better than the 2500k. The 4770k performs 6% better than the 4670k. The 5960x once again outperforms all of the CPUs listed.
Watch Dogs 2
Yikes. The 6300 performs 41% better than the 4300. The 8350 performs 18% better than the 6300 and 66% better than the 4300. That's pretty massive.
The 2600k performs 13% better than the 2500k. The 4770k performs 13% better than the 4670k. The 6700 performs 16% better than the 6600k. And once again, the 5960x is on top. COmparing it to the 6700, controlling for clock speeds, we see a 36% boost between the 8 core 5960x and the 6700. That's pretty significant.
I'm just gonna list from here on, not gonna do exact calculations, but I will give a little commentary.
The Division
I don't suspect there's much of a difference here on the AMD side, and I think a lot of the difference there can be explained by clock speed differences, although it looks like there is a small single digits, maybe 10% boost there.
On the intel side, with hyperthreading, we see very significant increases in minimum framerates, with once again the i7 5960x taking the cake.
Battlefield Hardline
On the AMD side, there seems to be a major difference between 4 and 6 cores, with much less difference between 6 and 8. On the intel side, hyperthreading seems to be negligible. Perhaps they reached a GPU bottleneck here, who knows. It's weird to see the 6 core i7 3970x perform similarly to the 4770k considering the major difference from 4300 to 6300.
Doom
There isnt much of a difference between the 4300 and 6300 but the 8350 seems to be performing extremely well. Hyper threading seems to add negligible performance.
So what can we conclude from this?
It looks to me that while not true in all games (I did look at other games that had next to no, to no performance with increased cores, some had GPU bottlenecks, others simply seemed to fail to utilize more than 4 cores), there does seem to be a trend toward increased multithreading in games. At the very least, an argument can be made when Ryzen comes out that getting a 6 core model looks like a good investment, since many games do seem to benefit significantly from the increased core count and even more with combined multithreading. Considering how the Ryzen 8 core models seem to be comparable to the 5960x based on early benchmarks, that might be worth it too.
There does seem to be less of a difference on average between 6 and 8 cores than there is between 4 and 6, but the difference still seems to exist in some cases.
Regardless, I'd say an argument can be made for buying CPUs with increased core count assuming the IPC is good. If it's crap like the FX series is compared to the i5s, of course quads are better, but assuming it's within, say, 20% of what intel offers, there's no reason to not go for the extra 2-4 cores. Considering how you'll be able to buy something similar to the i7 5960x (presumably) for the price of a quad core i7 and a 6 core for the price of an i5, I think a strong argument can be made for going for it.
This debate between more or fewer cores isn't new. This debate happened 10 years ago, when people were deciding between the core 2 duo e8400 or the core 2 quad q6600. The same architecture was used in both, but most went with the E8400 because it was cheaper and because it was clocked 25% higher. This might have sounded like a good investment at the time, but then games like Bad company 2, BF3, and others hit and the dual cores were severely lacking compared to the quads. Fast forward around 2-3 years later when the consoles came out 2013 with games like watch dogs and E8400 was basically useless. While it does appear there is a diminishing rate of returns with multithreading where even games that support it don't scale perfectly (we should see a 50% boost going to a 6 core and an additional 33% boost going to an 8 core), there is a boost nevertheless and it is significant.
Even if you have slightly less poerformance per thread and as such slightly less performance in some games, now, you'll likely still get a good 60 FPS in most situations and remember, what we really need to worry about in the future is games that actually do use more threads, and eventually REQUIRE those extra threads to function at all. The 8350 outperforms the 4300, period. The 5960x outperforms the i5s and i7s.
And when CPUs like the 5960x finally being affordable, I do think there is a reason to go for at least a 6 core if not an 8 core. This is especially true if you plan on using your system for a long time. Sure, you might be able to skimp now if you plan on upgrading 3-4 years from now anyway, but if you plan to use your CPU for a long time (more than 4 years) it would be worth getting more cores.
And yeah. I just decided to do this because I still see people pushing the whole "all you need is 4 cores" mentality with ryzen coming out when it seems that yes, games actually do use multithreading more than one would think. Not all games do it, but enough of them do where I think we'll see more multithreading becoming common in the next few years.
EDIT: TLDR: Some games do use more than 4 cores/threads and there is a significant performance increase in some games from having more cores/threads available. Furthermore it's reasonable to expect these trends to continue in the future, just as quad cores overtook duals in terms of performance. As such it is worth getting a CPU with more cores assuming it's performance per core isn't crap. AMD Ryzen can be a game changer in this regard.
Edit2: it should be noted I did not make these benchmarks. I can't test anything. I pulled them off of Google, and they originate from a Russian site that benchmarks games game gamegpu.ru. Please stop asking me to benchmark certain games or complaining about my testing methodology. Not my problem.
