Intel Second Generation Core i7 3820 Review

ccokeman - 2011-01-08 21:46:05 in CPU's
Category: CPU's
Reviewed by: ccokeman   
Reviewed on: March 15, 2012
Price: $320

Introduction:

Introduced back in November of 2011, Intel's Sandy Bridge Extreme processors came as a long-awaited update to the company’s high-end enthusiast line. Socket 1366 and the X58 chipset have served well, but at this point in time, even a mid-range 2600K Sandy Bridge-based system can really push past the performance of a quad-core Socket 1366 processor. Now a little long in the tooth, it is time for a refresh. At its onset, Intel's Sandy Bridge Extreme platform was catered to the upper crust of the market, with the 6-core Core i7 3960X priced at $999. The Core i7 3930K was released at around $550, but Sandy Bridge-E was still lacking a "value" option for mainstream consumers. That is, until the release of the quad-core Core i7 3820, which is priced at just over $300. Socket 1155 Sandy Bridge processors, like the Core i7 2600K, have already proven to be potent performers, so what makes the step up to the SNB-E i7 3820 appealing for the X58 or Socket 1155 owner? Off the bat, it sees an increase in PCIe lanes from 16 to 40, support for PCIe 3.0, quad-channel memory with support for up to 64 GB of total system memory, increased L3 cache and computing performance, a bump in frequency to 3.6 GHz, Turbo Boost 2.0, a partially-locked chip for Sandy Bridge-style overclocking, and new instruction sets. Will the partially-locked nature of the Core i7 3820 present a large enough incentive on performance alone or will the Enthusiast have to step up to a 6-core chip to reap in the rewards of the Extreme socket and X79 chipset?

Closer Look:

This Core i7 3820 sample arrives in a small black foam-padded box, sans all of the Intel retail packaging. While not indicative of what you will get at the store, it’s important to note that the Socket 2011 lineup all come without a cooling solution. The Second Generation Sandy Bridge-E Intel Core i7 3820 has 4 physical processor cores that support Intel Hyper Threading technology, which allows the chip to run up to 8 threads at a time. The CPU itself is built for use on motherboards using Intel's X79 chipset and LGA 2011 socket. This 32 nm chip has a die size of 294 mm2 or roughly two-thirds the size of the die used on the Core i7 3960X. It features 10 MB of onboard L3 cache, which is shared dynamically between the four processor cores and factory clocked to 3.6 GHz. Turbo Boost Technology 2.0 allows the Core i7 3820 to scale up to 3.9 GHz under certain workload scenarios. Much like the rest of the SNB-E lineup, the i7 3820 has an integrated memory controller that natively supports four channels of DDR3 1600 MHz system memory for increased bandwidth. Another unique feature of the Core i7 3820 is that it is a partially-unlocked chip. What this means is a multiplier that is locked to a maximum of 43x, initially limiting the potential overclock to 4300 MHz while using the default 100 MHz bclock. Using SNB-E’s exclusive "Gear Ratios" of 125 MHz and 166 MHz, however, it allows for some serious overclocking margins if you take the time to test the chip out. Additional top-line features are support for Intel AVX (Advanced Vector Extensions), SSE 4.1 and 4.2 instruction sets, and 40 PCIe lanes that meet the PCIe 3.0 specifications.

 

 

 

 

 

 

 

 

 

 

 

When compared to previous generation processors, the size of the LGA 2011 chip is absolutely huge to comparison to both the Socket 1366 and Socket 1155 chips. However with only four cores, no integrated graphics core, and 1.27 billion transistors on the Sandy Bridge i7 3820, the actual die size is smaller than the 3960X by about 33%, though it still retains the larger LGA 2011 package dimensions.

 

The Second Generation Core i7 Sandy Bridge Extreme processors are designed to work with a two-chip platform, with the bulk of the I/O on-die and the Platform Control hub taking care of the remaining functions. Coming off the Sandy Bridge-E processor are the four memory channels, each supporting a substantial increase in bandwidth to 12.8 GB/s. There are a total of 40 lanes of PCIe 3.0 graphics bandwidth, with each potentially carrying 1 GB/s of data, bi-directionally, and 8 GT/s (GigaTransfers per second) transfer rates on PCIe devices that support the speed. While not readily apparent on Intel’s specifications, a quick search reveals a good number of PCIe 3.0-compatible motherboards and graphics cards that support the updated interface, including the newly released Radeon HD7970. Multiple GPUs are supported in several configurations, which should improve multi-GPU performance. No longer will you have to sacrifice other PCIe device functionality due to a lack of PCIe lanes; eight lanes are now provided by the X79 PCH, on top of the 40 available from the CPU. A total of fourteen USB 2.0 ports, Intel Gigabit LAN, Intel HD Audio, and 6 SATA ports are attached to the X79 PCH as well.

 

Equipped with 2 fewer cores, 5 MB less L3 cache, and a billion less transistors than the 3960X, the Core i7 3820 looks to be a more direct comparison to the Core i7 2600K specification-wise, with the added advantage of a higher base clock speed of 3.6 GHz and quad-channel memory support. Let’s see if the Core i7 3820 is worthy of a step up to the extreme side and provides enough up-side to make the transition to Socket 2011.

Specifications:

2nd Generation Intel® Core™ i7 Processor Comparison
Core™ i7-3960X Processor
Extreme Edition
Core™ i7-3930K Processor
 
Core™ i7-3820 Processor
 
 
Number of Processor Cores
6
6
4
Number of Simultaneous Threads with Intel®
Hyper-Threading Technology
12
12
8
Intel® Smart Cache Size
15 MB
12 MB
10 MB
Processor Base Frequency
3.3 GHz
3.2 GHz
3.6 GHz
Memory Frequency
1600 MHz
1600 MHz
1600 MHz
Intel® Turbo Boost Technology
2.0
2.0
2.0
Number of DDR3 Memory Channels
4
4
4
Overclocking Enabled
Yes
Yes
Yes
Intel® Express Chipset
X79
X79
X79
Socket
LGA2011
LGA2011
LGA2011

 

Features:

 

 

All information courtesy of Intel

Testing:

Testing the Second Generation Intel Core i7 3820 Sandy Bridge Extreme will involve running it and its comparison products through OCC's test suite of benchmarks, which include both synthetic benchmarks and real-world applications. The gaming tests will also consist of both synthetic benchmarks and actual game play, in which we can see if similarly-prepared setups offer any performance advantages. The system will receive a fully updated, fresh install of Windows 7 Professional 64-bit edition, in addition to the latest drivers for each board and latest AMD Catalyst drivers for the XFX HD 6970. To ensure as few variables as possible, all hardware will be tested at their stock speeds, timings, voltages, and latencies, unless otherwise stated. Turbo Boost will be disabled on all processors to make a fair comparison without skewing the results.

 

Testing Setup: Intel Core i7 Socket 2011

 

Testing Setup: AMD AM3+

 

Testing Setup: Intel Core i5/i7 Socket 1155

 

Testing Setup: Intel Core i7 Socket 1366

 

 

Comparison CPUs:

 

Overclocking:

Overclocked settings:

 

When it comes to overclocking the Second Generation Core i7 3820, there are a few limitations, as it is a partially unlocked processor; not quite K spec, but not a base model either. By partially unlocking the chip, Intel has still catered to the enthusiast, though not giving up the reigns totally. The Core i7 3820 has a maximum clock multiplier of 43x. It means that the most you will see with the 100 MHz bclock is 4300 MHz or just a mere 400 MHz above the Turbo Boosted speeds delivered from factory. That, of course, will not do; not for an Enthusiast-grade platform. The 2600K and 2700K are able to hit well above this number for a comparable cost. On the Socket LGA 2011 X79 platform, Intel has given enthusiasts a tool that allows the CPU bclock to be adjusted up via a series of Gear Ratios that start at 100 MHz, all the way to 250 MHz. To get the most out of the Core i7 3820, I will have to use the bclock, Gear Ratios, and adjustments of the multiplier to levels lower than 43x. In my first run, I intended to see what kind of bclock tolerance the chip had. Eventually, I was able to push the bclock from 100 MHz to 107 MHz; a pretty decent bclock increase that allowed the chip to scale to 4.6 GHz. Again, this was not enough of a clock, as my 2600K does that easily. Next up was the 125 MHz Gear Ratio and multiplier adjustment; this moved the needle quite a bit higher to 5.0 GHz. Further bclock tuning up to 125.625 MHz gained a prime stable 5025 MHz clock speed from the chip. Further tuning of the bclock could have raised the bar even higher, though without the benefit of long term stability. Nonetheless, it was capable of running the entire benchmark suite at 5.1 GHz. Voltage tuning and enhanced cooling was needed to get these clock speeds, but nothing more extreme than what most would endeavour to use.

 

 

 

If overclocking is not in your future, Intel's Turbo Boost 2 technology is used to boost the speed of the processor under differing usage conditions. Low load situations with one or two cores active will see a boost of up to 600 MHz over the base clock speeds of 3300 MHz, or a total of 3900 MHz. With all cores active, you can expect a boost of up to 300 MHz for a total of 3600 MHz when fully loaded. Each of these scenarios offer a nice boost in clock speed, with really no effort, as the BIOS setting is enabled by default, allowing the end user the ability to overclock without really overclocking; Intel simply does it for you.

 

Maximum Core Clock Speed:

Each CPU has been tested for stability at the listed overclocked speeds. These clock speeds will represent the clock speed used in the overclocked scores for the testing.

 

 

Benchmarks:

  1. Apophysis
  2. WinRAR
  3. Geekbench 2.1
  4. Office 2007 Excel Number Crunch
  5. POV-Ray 3.7
  6. Bibble 5
  7. Sandra 2011
  8. AIDA64 1.85
  9. HandBrake .9.5
  10. ScienceMark 2.02
  11. Cinebench 10 & 11.5
  12. HD Tune 4.60
  1. Aliens vs. Predator
  2. Civilization V
  3. Battlefield: Bad Company 2
  4. 3DMark 11

Testing:

The first part of our testing will involve system-specific benchmarks.

 

Let's get started with Apophysis. This program is primarily used to render and generate fractal flame images. We will run this benchmark with the following settings:

 

 

The measurement used is time to render, in minutes, to completion.

 

 

 

 

 

 

 

 

 

  

Lower is Better

 

WinRAR is a tool that archives and compresses large files to a manageable size. Here, we will test the time needed to compress files of 100 MB and 500 MB. Time will be measured in seconds.

 

ZIP:

  

  

Lower is Better

 

 

RAR:

  

  

Lower is Better

 

Geekbench:

Geekbench 2.1 is a benchmark that tests CPU and memory performance in an easy-to-use tool. The measure used for comparison is the total suite average score.

  

  

Higher is Better

 

Bibble 5:

This test consists of converting one hundred 8.2 MP RAW images to JPEG format. The original file size is 837 MB. The measure used for comparison is time needed to convert the file, in seconds.

  

Lower is Better

 

In Apophysis, the Core i7 3820 is the fastest stock processor, based purely on clock speed alone. When overclocked, the i7 3820 and 2600K deliver similar results in this test. In the WinRAR testing, the i7 3820 performs well against the 2600K, which uses the same architecture. The Geekbench scoring shows that, as a platform, the i7 3820 and X79 chipset delivers a higher level of performance, while the Bibble 5 tests show how close the 2600K and 3820 are in terms of pure CPU performance.

Testing:

Office 2007 Excel Big Number Crunch: This test takes a 6.2 MB Microsoft Excel spreadsheet and performs about 28,000 sets of calculations that represent many of the most commonly used calculations in Excel. The measure of this test is the amount of time it takes to refresh the sheet.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

  

Lower Is Better

 

POV-Ray 3.7: This program features a built-in benchmark that renders an image using Ray Tracing. The latest versions offer support for SMP (Symmetric Multi-Processing), enabling the workload to be spread across several cores for quicker completion.

  

Higher Is Better

 

HandBrake .9.5: is an open source application used to transcode multiple video formats to an h.264 output format. The test file size is 128 MB in size and 43 seconds in length.

  

Lower Is Better

 

Throughout all of these tests, the i7 3820 and 2600K perform very similarly.

Testing:

SiSoft Sandra is a diagnostic utility and synthetic benchmarking program. Sandra allows you to view your hardware at a higher level to be more helpful. For this benchmark, I will be running a broad spectrum of tests to gauge the performance of key functions of the CPUs.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Processor Arithmetic

  

  

Multi-Core Efficiency

  

  

 

Memory Bandwidth

  

  

 

Cache and Memory

  

 

 

Power Management Efficiency

  

 

AIDA64 Extreme Edition: is a software utility designed for hardware diagnosis and benchmarking. I will be using the CPU Queen test that looks for the solution to the "Queens" problem on a 10x10 chessboard. This tests the branch prediction capabilities of the processor. The FPU Mandel test measures double precision floating point performance through computation of several frames of the "Mandelbrot" fractal.

  

  

Higher is Better

In all of stock frequency tests, the Core i7 3820 delivers a higher level of performance than the 2600K and significant improvements over the aged Core i7 920. When overclocked, these margins stay relative to each other, based on the core clock similarities between the i7 3820 and 2600K. In applications that can use it, the quad-channel memory bandwidth on the Core i7 3820 provides a significant point of difference to the dual-channel Core i7 2600K.

Testing:

ScienceMark tests real-world performance instead of using synthetic benchmarks. For this test, we run the benchmark suite and will use the overall score for comparison.

 

 

 

 

 

 

 

 

 

 

 

  

 

 

 

  

 

 

 

  

Higher is Better!

 

 

 

Cinebench 10 is useful for testing your system, CPU, and OpenGL capabilities using the software program, CINEMA 4D. We will be using the default tests for this benchmark.

 

  

 

  

Higher is Better

Cinebench 11.5

 

  

Higher is Better

 

HD Tune measures disk performance to easily make comparisons between drives or disk controllers.

 

  

 

  

Higher is Better

 

  

 

  

Lower is Better

 

PCMark 7 is the latest iteration of Futuremark's popular PCMark system performance tool. This latest version is designed for use on Windows 7 PCs and features a combination of 25 different workloads to accurately measure the performance of all PCs, from laptops to desktops.

  

  

Higher is Better

 

The Second Generation Core i7 3820 is much faster than the Socket 1366-based Core i7 920 in each and every one of these benchmarking tests. Against the Core i7 2600K, however, the overall performance margins are much smaller.

Aliens vs. Predator, developed by Rebellion Developments, is a remake of the classic science fiction first-person shooter from 1999. The game is based on the two popular sci-fi franchises: Alien and Predator. In this game, you have the option of playing through the single player campaigns as one of three species: the Alien, the Predator, or the Human Colonial Marine. The game uses Rebellion's Asura game engine, which supports Dynamic Lighting, Shader Model 3.0, Soft Particle systems, and Physics. For testing, I will be using the Aliens vs. Predator benchmark tool, using the settings listed below. All DirectX 11 features are enabled.

 

Settings

 

 

 

 

 

 

 

 

 

 

 

  

  

Higher = Better

 

The delivered FPS in Aliens vs. Predator do not vary much between stock and overclocked speeds, or between processor type and platform.

Testing:

Civilization V is a turn-based strategy game. The premise is to play as one of 18 civilizations and lead it from the "dawn of man" up to the space age. This latest iteration of the Civilization series uses a new game engine and brings massive changes to the AI behaviour. Released for Windows in September of 2010, Civilization V was developed by Firaxis Games and published by 2K Games. Testing will be done using actual gameplay, with FPS measured by Fraps through a series of five turns, 199-205 turns into the game.

Settings

 

 

 

 

 

 

 

 

 

 

 

 

  

  

Higher = Better

 

In three out of four tests, the Core i7 3820 performs at the higher end of the results spectrum.

Testing:

Battlefield: Bad Company 2 is a first-person shooter developed by EA Digital Illusions CE (DICE) and published by Electronic Arts for Windows, PS3, and Xbox 360. This game is part of the Battlefield franchise and uses the Frostbite 1.5 Engine, which allows for destructible environments. You can play the single-player campaign or multiplayer; the latter with five different game modes. Released in March 2010, it has sold in excess of six million copies so far.

Settings

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Although FPS does not vary much between processors and platforms, the X79-based configurations, including when equipped with the Core i7 3820, generally deliver improved gaming performance.

Testing:

3DMark 11 is the next instalment in Futuremark’s 3DMark series, with Vantage as its predecessor. The name implies the benchmark's focus on Microsoft DirectX 11 and in an unintended coincidence, matches the current year in number (which was the naming scheme to some prior versions of 3DMark nonetheless). 3DMark 11 was designed solely for DirectX 11, so Windows Vista or 7 is required alongside a DirectX 11 graphics card in order to run this test. The Basic Edition gives unlimited free tests on performance mode, whereas Vantage only allows for a single test run. The advanced edition costs $19.95 and unlocks nearly all features of the benchmark, while the professional edition runs for $995.00 and is mainly suited for corporate use. The new benchmark contains six tests, four of which are aimed only at graphical testing – one that tests physics handling, and one that combines graphics and physics testing together. The open source Bullet Physics Library is used for physics simulations and although not as mainstream as Havok or PhysX, it still remains a popular choice.

The new benchmark comes with two new demos that can be watched; both of which are based on the standard tests, though unlike them, contain basic audio. The first demo is titled "Deep Sea" and involves a number of vessels exploring what looks to be a sunken U-Boat. The second demo is titled "High Temple" and displays a location similar to South American tribal ruins, with statues and the occasional vehicle. The demos are simple in that they have no story, but really demonstrate testing conditions. The vehicles have the logos of the sponsors, MSI and Antec, on the sides, helping to make the basic edition free. The four graphics tests are slight variants of the demos. I will use the three benchmark test pre-set levels to find the performance of each card. The pre-sets are used because they are comparable to what can be run with the free version, so results can be compared across more than just a custom set of test parameters.

 

Settings

 

 

 

 

 

 

 

 

 

 

In five out of 6 tests, the Second Generation Core i7 3820 presents itself as the highest performing CPU in the comparison. In the one test that it did not finish first, the only processor to outperform it was the Second Generation Core i7 3960X. This shows how having the faster and additional PCIe lanes on the X79 platform really pays off.

Conclusion:

The Second Generation Core i7 3820 is a small step-up in terms of performance when compared to Intel's Socket 1155 platform. Originally, the release of the X79 platform was limited to 6-core chips that were priced from $550 up to $999; not the easiest cost pill to swallow when the top Sandy Bridge Socket 1155 chip was a mere $330. If a 6-core chip is a requirement for your system build, there is no better option out right now than Sandy Bridge-E. However, most users play at a lower cost point; even those on the "Extreme" side. This is where the cheaper i7 3820 comes in. At its very least, the 40+ PCIe 3.0 lanes should pay dividends for multi-GPU gamers who are looking at the next crop of video cards or to take advantage of the added memory bandwidth from 4 channels of DDR3 memory in excess of 2400 MHz. As a step up from the venerable Socket 1366 Core i7 920, the Core i7 3820 offers a massive leap in performance and is a viable upgrade choice over the Socket 1155 platform. It will cost a little more to transition towards LGA 2011, but with the Core i7 3820 going for $320 and quad-channel kits of DDR3 1600 MHz dropping below $100, the cost concerns are not that great.

When it comes to overclocking, the Second generation Core i7 3820 is a more-than-willing participant; more so than its partially-locked nature suggests. Using the maximum multiplier of 43x and stock bclock, 4300 MHz was easily achieved. Further tuning the bclock, whilst using the 100 MHz Gear Ratio, yielded a bump to 4.6 GHz with some voltage tuning. But wait, there’s more! Changing the Gear Ratio to the 125 MHz strap allowed for a maximum clock speed of up to 5375 MHz using the 43x multiplier. With the cooling I had, however, this was not going to happen for the long term, though just over 5 GHz was easy to reach with the right voltage tuning and cooling. In the end, I was able to pull 5025 MHz from this chip, using a bclock of 125.625 MHz x 40 and the same overclocking tweaks as other Sandy Bridge processors. It really could not be simpler to accomplish with such a willing chip.

Ultimately, the Second Generation Core i7 3820 does what it is supposed to, and offers up a measurable leap in performance over Socket 1366 X58 platform-based processors such as the Core i7 920. As an upgrade over the current crop of Socket 1155 processors, the change is not as great, due to the use of the same architecture. However, in applications where users can utilize large quantities of quad-channel memory and for gamers who can use the additional faster PCIe lanes, stepping up to Sandy Bridge-E is definitely the way to go, especially when the Core i7 3820 offers an excellent price point to jump at.

 

Pros:

 

Cons: