Is a high-end CPU a real need for a gaming computer?

[nextpage title=”Introduction”]

One of the most common questions any computer expert is used to hearing is if it’s worth it to spend more money investing in a high-end CPU when you are building a gaming computer. Today, we will test if a high-end processor can bring more performance in games (i. e., frames per second) than a mainstream or even a basic one. Check it out!

First of all, it is important to keep in mind that, as in the former tests, this test has the only objective to satisfy our curiosity. We’re testing a myth. And the tested CPUs are not direct competitors, since we included a discontinued processor and some CPUs from different price ranges, that are not direct competitors.
It is also important to remember that the Core i7-4770K is not, obviously, the most high-end CPU available today, since there are newer models like the Core i7-4790K, the Core i7-5775C, the Core i7-6700K, and even the socket LGA2011-v3 CPUs like the Core i7-5960X. But the Core i7-4770K is still a high-end processor, at least for the purpose we are testing it.
As we are trying to see if it’s worth it to buy a high-end CPU for a budget-conscious gaming computer, we chose to use a mainstream video card (a GeForce GTX 750) and disable the integrated video. We made this decision because, if you can afford one, you are probably not worried about spending some more bucks on the CPU. So, the question we are actually trying to answer is if is a high-end CPU a good investment when you are using an average video card or, in other words, if the CPU is a “bottleneck” when you build a computer with a mainstream video card.

Besides the Core i7-4770K (a high-end CPU), we included a Core i3-4150 (mainstream), a Pentium G3320 (entry-level) and a Core 2 Quad Q8300 (representing the old mainstream/high-end CPUs). Unfortunately, we did not have an available Core i5 CPU at the time we collected the data. We also did not include AMD processors because we are not trying to compare different brands, just to bust a myth (or to confirm it).

Figure 1 shows one of the processors we used: the Core i3-4150, which is a typical average CPU nowadays.

Figure 1: one of the CPUs tested

Let’s compare the main specs of the reviewed CPUs in the next page.
[nextpage title=”The Reviewed CPUs”]
In the tables below, we compare the main features of the CPUs included in our review.

CPU	Cores	HT	IGP	Internal Clock	Turbo Clock	Core	Tech.	TDP	Socket
Core i7-4770K	4	Yes	Yes	3.5 GHz	3.9 GHz	Haswell	22 nm	84 W	LGA1150
Core i3-4150	2	Yes	Yes	3.5 GHz	No	Haswell	22 nm	54 W	LGA1150
Pentium G3220	2	No	Yes	3.0 GHz	No	Haswell	22 nm	53 W	LGA1150
Core 2 Quad Q8300	4	No	No	2.5 GHz	No	Yorkfield	45 nm	95 W	LGA775

Below you can see the memory configuration for each CPU.

CPU	L2 Cache	L3 Cache	Memory Support	Memory Channels
Core i7-4770K	4 x 256 kiB	8 MiB	Up to DDR3-1600	Two
Core i3-4150	2 x 256 kiB	3 MiB	Up to DDR3-1600	Two
Pentium G3220	2 x 256 kiB	3 MiB	Up to DDR3-1333	Two
Core 2 Quad Q8300	4 MiB	No	Up to DDR3-1066*	Two*

* On LGA 775 CPUs, the memory controlled was located at the chipset, not at the processor. So, those characteristics refer to the Intel G41 chipset.
[nextpage title=”How We Tested”]
During our benchmarking sessions, we used the configuration listed below. Between our benchmarking sessions, the only variable device was the CPU being tested and the motherboard, which had to be replaced to match the different CPUs.
Hardware Configuration

Motherboard (Core 2 Quad Q8300): Gigabyte G41MT-ES2L
Motherboard (Core i7-4770K, Core i3-4150 and Pentium G3220): ASRock Z97 Extreme4
CPU Cooler: Intel stock
Memory: 8 GiB DDR3-2133, two G.Skill Ripjaws F3-17000CL9Q-16GBZH 4 GiB memory modules configured at 1,066 MHz, 1,333 MHz or 1,600 MHz depending on the maximum speed supported by the CPU
Boot drive: Kingston HyperX Savage 480 GB
Video Card: Gigabyte GeForce GTX 750 (GV-N750OC-1GI)
Video Monitor: Philips 236VL
Power Supply: Corsair CX500M

Operating System Configuration

Windows 7 Home Premium 64-bit
NTFS
Video resolution: 1920 x 1080 60 Hz

Driver Versions

NVIDIA driver version: 353.3
Intel Inf chipset driver version: 10.0

Software Used

Error Margin
We adopted a 4% error margin. Thus, differences below 4% cannot be considered relevant. In other words, products with a performance difference below 4% should be considered as having similar performance.
[nextpage title=”Battlefield 4 and Dirt Rally”]

Battlefield 4

Battlefield 4 is the latest installment in the Battlefield franchise, released in 2013. It is based on the Frostbite 3 engine, which is DirectX 11. In order to measure performance using this game, we walked our way through the first mission, measuring the number of frames per second three times using FRAPS. We ran this game at 1920 x 1080, setting overall image quality at “high.”
The results below are expressed in frames per second (fps) and they are the mean between the three collected results.

In this test, it is clear that all the tested CPUs had the same performance.

Dirt Rally

Dirt Rally is an off-road racing game released in April 2015, using Ego engine. To measure performance using this game, we ran the performance test included in the game, in 1920 x 1080 (Full HD) resolution and image quality configured as “high” and MSAA off.
The results below are expressed in frames per second (fps).

In this game, the performance of the Core i7-4770K was similar to the Core i3-4150’s, 12% superior to the Pentium G3320’s, and 57% superior to the Core 2 Quad’s.

[nextpage title=”Dragon Age: Inquisition and Dying Light”]

Dragon Age: Inquisition

Dragon Age: Inquisition is the most recent game from the popular action RPG franchise Dragon Age. It was launched in November 2014 and uses the Frostbite 3 engine with SpeedTree.
We ran the game at 1920 x 1080 (Full HD), with all quality options at “medium”, measuring three times the framerate with FRAPS.
The results below are expressed in frames per second and represent the arithmetical mean of the three collected results.
On Dragon Age: Inquisition, the Core i7-4770K had the same performance of the Core i3-4150, was 30% faster than the Pentium G3220, and 44% faster than the Core 2 Quad Q8300.

Dying Light

Dying Light is an open-world horror game launched in January 2015, using the Chrome Engine 6. We tested the performance at this game with all quality options at “medium”, at 1920 x 1080 (Full HD), measuring three times the framerate using FRAPS.
The results below are expressed in frames per second (fps) and they are the mean between the three collected results.

On this game, the Core i7-4770K was 8% faster than the Core i3-4150, 19% faster than the Pentium G3220, and 45% faster than the Core 2 Quad Q8300.

[nextpage title=”GTA V and The Witcher 3: Wild Hunt”]

GTA V

Grand Theft Auto V, or simply GTA V, is a open-world action game released for PCs in April of 2015, using the RAGE engine. In order to measure the performance on this game, we ran the performance test of the game, measuring the framerate with FRAPS. We ran GTA V at 1920 x 1080, with image quality set to “normal”.

The results below are expressed in frames per second.

This game ran on the Core i7-4770K with a framerate 12% higher than on the Core i3-4150, 89% higher than on the Pentium G3220, and 98% higher than on the Core 2 Quad Q8300.

The Witcher 3: Wild Hunt

The Witcher 3: Wild Hunt is an open-world RPG, released in May of 2015 and based on the REDengine 3 engine. In order to measure the performance on this game, we walk around at the first scene of the game, measuring the framerate with FRAPS three times. We ran the game at Full HD (1920 x 1080), with image quality set to “medium”.

The results below are expressed in frames per second (fps) and they are the mean between the three collected results.

On this game, all the CPUs performed the same way.

[nextpage title=”Conclusions”]
After testing the performance on six different modern games, maintaining a mainstream video card (GeForce GTX 750) and changing only the CPU, the conclusion was crystal clear. In two of those games, the four CPUs performed the same way. In other two games, the Core i7-4770K had the same performance of the Core i3-4150 (while the other CPUs has inferior performance), and, in two games, the Core i7-4770K showed a small advantage over the Core i3-4150.
So, it seems to be clear the, using an average video card, a mainstream CPU like the Core i3-4150 represents no “bottleneck” on most games, and a more expensive CPU like the Core i7-4770K brings zero or very little benefit to the framerate on most games. This is because the most important difference, nowadays, from a mainstream CPU to a high-end one is the number of available cores (or threads), and it is clear that most games do not use more than four threads. It has been clear when we tested the Core i7-5960X.
Now we can confirm something every computer expert always says: if you are building a gaming computer with a limited budget, it is better to buy a mainstream processor (using the saved bucks to buy a better video card) than spending it on an expensive CPU.
In some cases, even an entry-level CPU like the Pentium G3220, or an old processor like the Core 2 Quad Q8300, does the job just fine. However, if you are building a new computer for gaming, we do not recommend those options: in some games, you will lose performance; and probably, new titles will demand more processing power in the near future.
It is important to keep in mind that or conclusions can not be equally applicable on a computer with a high-end video card, where a mainstream CPU can represent a performance bottleneck. If is it the case, however, the user probably has a larger budget and do not even think about buying a basic or average CPU.