A8-3870K vs. Core i3-2105 CPU Review
By Gabriel Torres on January 18, 2012


Introduction

AMD released recently its highest-end CPU with integrated video, the A8-3870K “Black Edition,” which comes with its clock multiplier unlocked, giving you an extra overclocking option. In this review, we will compare it to the A8-3850 and to its main competitors from Intel: the Core i3-2105 and Core i3-2100.

It is interesting to see AMD starting to use the same letter as Intel to indicate its CPUs with an unlocked clock multiplier.

AMD calls their CPUs with integrated video controller “APUs” (Accelerated Processing Units). In our articles and reviews, we will still be calling these products “CPUs.” For a more detailed overview of the A8 series from AMD, please read our “A8-3850 vs. Core i3-2100 CPU Review.”

A8-3870K vs. Core i3-2105
click to enlarge
Figure 1: The A8-3870K and the Core i3-2105

A8-3870K vs. Core i3-2105
click to enlarge
Figure 2: The A8-3870K and the Core i3-2105

The Reviewed CPUs

In the tables below, we compare the main features of the CPUs included in our review. The CPUs from Intel support the SSE4 instruction set (both SSE4.1 and SSE4.2), which is not available on the AMD CPUs included in our review. The Intel CPUs included in our review are dual-core, but since they support Hyper-Threading (HT) technology, which simulates one additional core per CPU physical core, the operating system “sees” this CPU as having four cores.

CPU

Cores

HT

SSE4

IGP

Internal Clock

Turbo Clock

Base Clock

Core

Tech.

TDP

Socket

Price

A8-3850

4

No

No

Yes

2.9 GHz

No

100 MHz

Stars

32 nm

100 W

FM1

USD 140

A8-3870K

4

No

No

Yes

3.0 GHz

No

100 MHz

Stars

32 nm

100 W

FM1

USD 145

Core i3-2100

2

Yes

Yes

Yes

3.1 GHz

No

100 MHz

SandyBridge

32 nm

65 W

1155

USD 125

Core i3-2105

2

Yes

Yes

Yes

3.1 GHz

No

100 MHz

Sandy Bridge

32 nm

65 W

1155

USD 135

Prices were researched at Newegg.com on the day we published this review. TDP stands for Thermal Design Power and states the maximum amount of heat the CPU can dissipate. The CPU cooler must be capable of dissipating at least this amount of heat.

Below you can see the memory configuration for each CPU. During our review, we used DDR3-1866 memory modules.

CPU

L1 Cache

L2 Cache

L3 Cache

Memory Support

Memory Channels

A8-3850

64 KB + 64 KB per core

1 MB per core

No

Up to DDR3-1866

Two

A8-3870K

64 KB + 64 KB per core

1 MB per core

No

Up to DDR3-1866

Two

Core i3-2100

32 KB + 32 KB per core

256 kB per core

3 MB total

Up to DDR3-1333

Two

Core i3-2105

32 KB + 32 KB per core

256 kB per core

3 MB total

Up to DDR3-1333

Two

Below we have a quick comparison of the video engine of the CPUs.

CPU

Video Engine

DirectX

Clock

Cores

A8-3850

Radeon HD 6550D

11

600 MHz

400

A8-3870K

Radeon HD 6550D

11

600 MHz

400

Core i3-2100

Intel HD 2000

10.1

850 MHz

6

Core i3-2105

Intel HD 3000

10.1

850 MHz

12

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 CPU sockets.

Hardware Configuration

Operating System Configuration

Driver Versions

Software Used

Error Margin

We adopted a 3% error margin. Thus, differences below 3% cannot be considered relevant. In other words, products with a performance difference below 3% should be considered as having similar performance.

PCMark 7

PCMark 7 performs a series of tests and gives scores in the following categories: An overall score called PCMark; a Productivity score, which is the system performance when using applications such as web browsing and home office applications; a Creativity score, which is the system performance when viewing, editing, converting, and storing photos and videos; an Entertainment score, which is the system performance when recording, viewing, streaming, and converting TV shows and movies, importing, organizing, and browsing music, and gaming; and a Computation score, which indicates the processing performance of the system. Let’s analyze the results.

A8-3870K vs. Core i3-2105

The Core i3-2105 achieved an overall score 12% higher than the one achieved by the A8-3870K, while the Core i3-2100 achieved an overall score 7% higher. Here both CPUs from AMD achieved a similar performance level.

A8-3870K vs. Core i3-2105

On the productivity benchmark, the Core i3-2100 achieved a score 7% higher than A8-3870K’s, with the Core i3-2105 achieving a score 4% higher. The A8-3870K and the A8-3850 achieved comparable performance levels.

A8-3870K vs. Core i3-2105

On the creativity benchmark, the Core i3-2105 achieved a score 11% higher than A8-3870K’s, while the Core i3-2100 achieved a score 8% higher. Again, both CPUs from AMD achieved similar scores.

A8-3870K vs. Core i3-2105

On the entertainment benchmark, however, the A8-3870K achieved the highest score, 5% higher than Core i3-2105’s and 15.3% higher than Core i3-2100’s. Again, both CPUs from AMD achieved similar scores.

A8-3870K vs. Core i3-2105

On the computation benchmark, the Core i3-2105 achieved a score 13% higher than A8-3870K’s, with the Core i3-2100 achieving a score 4% higher than this CPU. Again, both CPUs from AMD achieved similar scores.

VirtualDub

With VirtualDub, we converted a full-length DVD movie to DivX format and saw how long it took for this conversion to be completed. DivX codec is capable of recognizing and using not only more than one CPU (i.e., more than one core) but also the SSE4 instruction set.

The movie we chose to convert was “Star Trek – The Motion Picture: Director’s Cut.” We copied the movie to our hard disk drive with no compression, so the final original file on our HDD was 6.79 GB. After compressing it with DivX, the final file was only 767.40 MB, which is quite remarkable.

The results below are given in seconds, so the lower the better.

A8-3870K vs. Core i3-2105

On DivX encoding, all CPUs achieved close performance levels, with the Core i3-2105 4% faster than the A8-3870K.

Photoshop CS4

The best way to measure performance is by using real programs. The problem, though, is creating a methodology using real software that provides accurate results. For Photoshop CS4, there is a methodology created by the folks at GamingHeaven that is very accurate. Their script applies a series of 15 filters to a sample image, and we wrote down the time taken for each filter to run. At the end, we had the results for each individual filter. We simply added them up to have the total time taken to run the 15 filters from the GamingHeaven batch. The results below are given in seconds, so the lower the number the better.

A8-3870K vs. Core i3-2105

On Photoshop CS4, the Core i3-2105 was 37% faster than the A8-3870K, and the Core i3-2100 was 34% faster than the A8-3850. Both AMD CPUs achieved the same performance level.

After Effects CS4

After Effects is a very well-known program for video post-production that is used to add animation and visual effects in videos. To evaluate the performance of each CPU running this program, we ran a workload consisting of a number of compositions that applied several filters and effects to a variety of input file types such as PSD (Photoshop), AI (Illustrator), EPS and TIF. After each filter was applied, the composition was rendered to an uncompressed AVI file with the same resolution as the input files. The results below are the time each CPU took to finish the whole batch, given in seconds, so the lower the number the better.

A8-3870K vs. Core i3-2105
On After Effects CS4, the Core i3-2105 and Core i3-2100 achieved the same performance level, and were 18% faster than the A8-3870K. The A8-3870K was 5% faster than the A8-3850 on this program.

Media Espresso 6.5

Media Espresso is a video conversion program that uses the graphics processing unit of the video card to speed up the conversion process. It is also capable of using Intel’s QuickSync technology available in the CPUs from this company. We converted a 449 MB, 1920x1080i, 18,884 kbps, MPG2 video file to a smaller 640x360, H.264, .MP4 file for viewing on a portable device such as an iPhone or iPod Touch.

A8-3870K vs. Core i3-2105

Here the Core i3-2105 was 59% faster than the A8-3870K, and the Core i3-2100 was 56% faster than this CPU. Both CPUs from AMD achieved the same performance level. This test shows us how powerful the Intel QuickSync technology is.

WinZip

We used WinZip not only to measure compression time, but also decryption time. We measured the time each CPU took to decompress and decrypt 200 JPEG images, 125 of them at 10 megapixels and 75 of them at six megapixels. The total size of all the photos was around 830 MB. The results below are given in seconds, so the lower the number the better.

A8-3870K vs. Core i3-2105
Decompressing and decrypting files, the Core i3-2100 was 33% faster than the A8-3870K, while the Core i3-2105 was 27% faster than this CPU. Both CPUs from AMD achieved the exact same performance.

iTunes

We used iTunes to convert an uncompressed .wav file into a high-quality (160 Kbps) MP3 file, and checked how many seconds each CPU took to perform this operation. Therefore, the results below are given in seconds, so the lower the number the better.

A8-3870K vs. Core i3-2105

Here the two CPUs from Intel were, again, faster than their competitors from AMD. The Core i3-2105 was 18% faster than the A8-3870K, while the Core i3-2100 was 12% faster than this CPU. The two CPUs from AMD achieved the same performance.

Cinebench 11.5

Cinebench 11.5 is based on the 3D software Cinema 4D. It is very useful to measure the performance gain given by having more than one CPU installed on the system when rendering heavy 3D images. Rendering is one area in which having more than one CPU helps considerably, because usually, rendering software recognizes several CPUs. (Cinebench, for instance, can use up to 16 CPUs.)

Since we were interested in measuring the rendering performance, we ran the test called “Rendering x CPUs,” which renders a “heavy” sample image using all available CPUs or “cores” – either real or virtual – to speed up the process. (On CPUs with Hyper-Threading technology, each core is recognized as two cores by the operating system.)

A8-3870K vs. Core i3-2105
Here the advantage switched to the CPUs from AMD, since they are quad-core parts, while the CPUs from Intel are dual-core products with Hyper-Threading technology. Here the two CPUs from AMD achieve the same performance level, and the A8-3870K was 15% faster than the Core i3-2100 and 17% faster than the Core i3-2105.

Call of Duty 4

Call of Duty 4 is a DirectX 9 game implementing high-dynamic range (HDR) and its own physics engine. We ran this game at 1440x900 with all image quality settings at their minimum values (no anti-aliasing and no anisotropic filtering). We used the game internal benchmarking feature, running a demo provided by NVIDIA called wetwork. We are putting the demo for downloading here if you want to run your own benchmarking. The game was updated to version 1.7. We ran this test five times, discarding the lowest and the highest scores. The results below are an arithmetic average of the three remaining values, given in frames per second (FPS).

We ran this game twice with each CPU. First, we used the CPU integrated graphics. Then we added a Radeon HD 6570 video card, which is an entry-level DirectX 11 video card. The CPUs from AMD included in this review allow you to combine the integrated graphics chip inside the CPU with the Radeon HD 6570 video card in CrossFireX mode in order to increase the performance.

A8-3870K vs. Core i3-2105

The integrated graphics processor of the A8-3870K was 46% faster than the one from the Core i3-2100 and 44% faster than the one from the Core i3-2105, and achieved the same performance as the A8-3850’s.

When we added a Radeon HD 6570, the video performance of the A8-3870K increased 44 percent. With this video card installed, this CPU was 28% faster than the Core i3-2105 and 32% faster than the Core i3-2100, also with the Radeon HD 6570 installed.

StarCraft II: Wings of Liberty

StarCraft II: Wings of Liberty is a very popular DirectX 9 game released in 2010. Though this game uses an old version of DirectX, the number of textures that can be represented on one screen can push most of the top-end graphics cards to their limits (especially when the graphics settings are set at “Ultra”). StarCraft II: Wings of Liberty uses its own physics engine that is bound to the CPU and thus does not benefit from PhysX.

We tested this game at 1440x900. The quality of the game was set to the “high” preset, disabling both anti-aliasing and anisotropic filtering. We then used FRAPS to collect the frame rate of a replay on the “Unit Testing” custom map. We used a battle between very large armies to stress the video cards.

A8-3870K vs. Core i3-2105

Here the integrated graphics processor of the A8-3870K was 75% faster than Core i3-2105’s and 77% faster than the Core i3-2100’s. It was also 7% faster than A8-3850’s. In fact, the performance achieved by these CPUs from AMD will allow you to play this game at the published settings at a very good performance.

When we added a Radeon HD 6570, the video performance of the A8-3870K increased 41 percent. With this video card installed, this CPU was 22% faster than the Core i3-2105 and 24% faster than the Core i3-2100, also with the Radeon HD 6570 installed.

Far Cry 2

Released in 2008, Far Cry 2 is based on a game engine called Dunia, which is DirectX 10. We used the benchmarking utility that comes with this game, setting video resolution to 1440x900, overall image quality to “high” (this  is the lowest possible setting if you want to run this game at DirectX 10), setting all “Performance” options to “low,” disabling both anti-aliasing and anisotropic filtering, and running the demo “Ranch Long.” The results below are expressed in frames per second.

A8-3870K vs. Core i3-2105

Here the A8-3870K was 33% faster than the Core i3-2100 and the Core i3-2105, achieving the same performance level of the A8-3850.

When we added a Radeon HD 6570, the video performance of the A8-3870K literally doubled. With this video card installed, this CPU was 43% faster than the Core i3-2105 and 39% faster than the Core i3-2100, also with the Radeon HD 6570 installed.

Battlefield 3

Battlefield 3 is the latest installment in the Battlefield franchise released in 2011, and is based on the Frostbite 2 engine, which is DirectX 11. In order to measure performance using this game, we walked our way through the first half of the “Operation Swordbreaker” mission, measuring the number of frames per second using FRAPS. We ran this game at 1440x900, minimizing all image quality settings, disabling both anti-aliasing and anisotropic filtering.

A8-3870K vs. Core i3-2105

You can’t run Battlefield 3 on the included Intel CPUs because it is a DirectX 11 game, and these CPUs are DirectX 10.1.

However, even though the CPUs from AMD are DirectX 11, they can’t run this game at a playable frame rate, even with all image quality settings minimized.

When we added a Radeon HD 6570, the video performance of the A8-3870K increased 62 percent. With this video card installed, this CPU was 29% faster than the Core i3-2105 and 36% faster than the Core i3-2100, also with the Radeon HD 6570 installed. Please note that even with this video card installed, you won’t be able to play this game due to the low performance achieved.

3DMark 11 Professional

3DMark 11 measures Shader 5.0 (i.e., DirectX 11) performance. Since the integrated graphics engine of the Intel CPUs included in this review is not DirectX 11, they can’t run this program. We ran this program at 1440x900 using the “Performance” profile.

This program provides three different scores: graphics, physics and combined.

A8-3870K vs. Core i3-2105

With a Radeon HD 6570 installed, the video performance of the A8-3870K increased 51%, and this CPU was 13% faster than the Core i3-2105 and 18% faster than the Core i3-2100.

A8-3870K vs. Core i3-2105

The physics score measures exclusively the physics performance of the system. Here all CPUs achieved the same performance level.

A8-3870K vs. Core i3-2105
The combined score shows a balance between the graphics and the physics performance achieved by each system being tested. With a Radeon HD 6570 installed, the video performance of the A8-3870K actually decreased a little, and the Core i3-2105 achieved a score 56% higher than the A8-3870K, with the Core i3-2100 achieving a score 31% higher than this CPU.

Overclocking

Since the A8-3870K comes with its clock multiplier unlocked, this gives us an extra option to push the clock of this CPU. Its default clock multiplier is x30 with a base clock of 100 MHz, generating its internal clock of 3 GHz (100 MHz x 30). We were able to easily increase the clock multiplier to x34.

Increasing the base clock, however, was very difficult, at least with the motherboard we had available (Gigabyte GA-A75M-UD2H). This is because all clocks on the system (integrated memory controller, PCI Express lanes, SATA ports, graphics controller, memory, etc.) are tied to the CPU base clock.

We could increase the base clock only up to 108 MHz, but since we had the clock multiplier at x34, we could put our A8-3870K to run stable at 3,672 MHz, an impressive 22.4% increase in the CPU’s internal clock rate.

Conclusions

The A8-3870K is very similar to the A8-3850 in price and specifications. It costs only USD 5 more than the A8-3850 and has almost the same clock rate (3 GHz vs. 2.9 GHz), but has a far better overclocking potential, thanks to its unlocked clock multiplier.

As the A8-3850, the A8-3870K has the best integrated video solution we’ve seen so far, beating its competitors from Intel really hard.

Also on the good side, applications that perform better with four “real” cores will perform better on the A8-3870K and A8-3850 than on the Core i3-2100 and Core i3-2105, which have only two “real” cores and two “simulated” ones, using Hyper-Threading technology.

The bad news is that aside from gaming, 3D rendering, and overclocking, the Core i3-2100 and Core i3-2105 are faster and, depending on the application, by a large margin. They also cost less.

So, if you are a gamer or an overclocker on a really tight budget, the new A8-3870K is a really nice option. But if you are an average user who won’t play games, the Core i3-2105 and the Core i3-2100 are far better options.

Originally at http://www.hardwaresecrets.com/article/A8-3870K-vs-Core-i3-2105-CPU-Review/1470


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