The Bottom Line
Introduction, Specifications, and Pricing
Intel's Skylake-X 10-core 20-thread i9-7900X was an impressive CPU at its launch. It was not only one of the fastest CPUs Intel had ever launched, but it implemented a new mesh interconnect that promised better core to core communication, and cache hierarchy reorganization that Intel said was crucial to enhancing the performance of high core count CPUs.
However, Intel also teased the first 1-teraflop consumer CPU, the monstrous 18-core i9-7980XE, and today we will show you what that CPU has to offer. While Intel's competition has upped the ante with a 16 core CPU at the same price as Intel's 10-core CPU, Intel is aiming to take back the multi-core performance crown from the competition with their new CPUs.
Let's see what the 7980XE and 7960X CPUs have to offer.
Specifications
The i9-7980XE (18C/36T) and 7960X (16C/32T) have base frequencies of 2.6GHz and 2.8GHz respectively, however, they will run at 3.4GHz and 3.7GHz respectively if a load is applied to all cores. With both CPUs Turbo Boost 2.0 Technology offers 4.2GHz if two cores are loaded, 4GHz if four cores are loaded, and 3.9GHz if 12 cores are loaded.
The 7980XE will run 3.5GHz on up to 16 cores, and the 7960X will run 3.6GHz on up to 16 cores. Turbo Boost 3.0 offers 4.4GHz on two cores on both CPUs. Both CPUs also have 165W TDPs and are fully unlocked. Both CPUs offer 44 PCI-E 3.0 lanes. The 7980XE offers 24.75MB of L3 cache, and the 7960X offers 22MB of L3 cache.
Pricing
The Core i9-7980XE is priced at $1999, making it one of the most expensive CPUs on the market. The 7960X is priced at $1,699, which is the same price as the older 10-core 6950X.
The CPUs and Test Setup
The CPUs
The 7980XE is on the left, and the 7960X is on the right, both of them look identical, and you wouldn't be able to tell them apart except for the frequencies listed on the front of the CPU. The top internal heat spreader of the CPU on the 7980XE and 7960X is the same as that on the 7900X and other Skylake-X CPUs.
There is a tiny inactive RFID chip in the top right corner of each CPU; it's a holdover from enterprise Xeons, which these CPUs are based on (presumably for easy identification of a CPU when there are thousands).
Intel used thermal paste instead of solder between the die and the heat spreader, but the die is larger on the high core count (HCC) CPUs (like 7980XE), so the die makes more contact with the heat spreader than the die of a 7900X would.
The bottoms of the CPUs are identical. The 7980XE is on the left while the 7960X is on the right. There are 2066 gold pads that make contact with the pins in the LGA socket, and when installing the CPU, do your best to try to avoid touching them.
Test Setup
- CPU: Intel Core i9-7980XE and i9-7960X
- Motherboard: One of the two below
- Cooler: Corsair H115i AIO Water Cooler
- Memory: Corsair Dominator Platinum 32GB and G.Skill TridentZ RGB 32GB
- Video Card: NVIDIA GeForce GTX 1080 Ti - Buy from Amazon / Read our review
- Storage - Boot Drive: Samsung 950 Pro 256GB M.2
- Storage - USB Drive: Corsair Voyager GS 64GB - Buy from Amazon / Read our review
- Case: Corsair Obsidian 900D - Buy from Amazon / Read our review
- Power Supply: Corsair RM1000 - Buy from Amazon / Read our review
- OS: Microsoft Windows 10 - Buy from Amazon
- Monitor: ASUS PA328 ProArt 32" 4K - Buy from Amazon
- Keyboard: Corsair K70 LUX - Buy from Amazon
- Mouse: Corsair M65 PRO RGB - Buy from Amazon / Read our review
- Headset: Corsair VOID RGB Wireless - Buy from Amazon / Read our review
I used the ASUS X299 ROG Rampage VI Extreme motherboard for a lot of the testing in this review (I used the MSI board below for the rest). It makes RGB LEDs classy. The Rampage is part of ASUS's second wave of X299 motherboards, so it's a bit more tuned for the HCC (12C+) CPUs.
MSI's X299 XPower was also used in this review, mainly because it was already on the test bench for review when I started doing a lot of the testing for this review. It's part of MSI's second wave of X299 motherboards, so it has improved VRM cooling and improved VRM design (more phases). No matter the heat sink design, I still used a fan over both of the motherboards' VRMs, as I needed active cooling on the test bench.
While all the tests are run at stock, one set of results, the 7980XE 4.4G OC, uses the overclock you see above. It involved 2.1v VCCIN, LLC Level 7, 1.200v VCore, 240A current capability, extreme VRM settings, and maxed out CPU power. The voltage is still a bit too much for the AIO to handle, so the CPU does throttle in certain situations.
Out of the Box Performance: CINEBENCH, wPrime, and AIDA64
The 7980XE and 7960X both show potential in CINEBENCH single and multithreaded performance. While they are faster than the competition, they cost a significant amount more. I should mention that the overclock result does throttle in some benchmarks, and it's due to CPU temperature, as even at 4.4GHz and 1.2v, the CPU gets very hot. If we look at wPrime, the 16 core Intel and AMD chips are very close, while two extra cores chop off a few seconds.
Overclocking the CPU brought in really great results in wPrime. AIDA64 FPU results (I did look at double precision FLOPS, and they were close to 1TFLOP, ~970GFLOPS) are very promising. However, AIDA64 did mention that results with Skylake-X aren't optimized (so they could be a bit buggy). Memory bandwidth when overclocked with XMP (3600MHz C16) are impressive, as are memory latency results.
Out of the Box Performance: Handbrake Video Transcoding, ScienceMark, and SuperPI
HandBrake isn't all about having more cores, in fact, I haven't been able to saturate either a ThreadRipper CPU or an HCC Intel CPU with the program. Instead, it spreads the load among cores, and it tends to like frequency over core count. It also depends on how you use the program. The 1950X beats out the 7980XE and 7950X when reducing a 4K video to 1080P, but loses against all Skylake-X CPUs when transcoding a 720P movie from one codec to another.
HandBrake likes frequency among other things, and that is why the 7960X beats the 7980XE when downgrading the 4K video to 1080P and when transcoding a 720P video from one codec to another.
ScienceMark also enjoys frequency, and it doesn't recognize more than 32 cores (it's more of a legacy benchmark), so the 7980XE is a bit gimped by the benchmark. The 7980XE and 7960X have the same 4.4GHz two core boost, so they should have the same single performance results, but the 7980XE has more cache.
Out of the Box Synthetic Gaming Performance: UNIGINE and 3DMark
The 7980XE and 7960X are pretty equal in FireStrike, and it does seem that the benchmark enjoys the extra cores and Intel's microarchitecture. CloudGate seems to prefer frequency over cores.
Unigine also really takes advantage of frequency, but the effect is more evident at 720P and less of an issue during 1080P benching. These results show us that some games will enjoy the more cores of the 7980XE, while others will like the frequency of the 7960X.
Out of the Box Gaming Performance: Resident Evil, Tomb Raider, GTA:V, Ashes of the Singularity
Resident Evil seems to prefer frequency over cores, but the overclocked 7980XE takes the crown as usual. While GTA:V seems to like the combination of cores and frequency, and the 7980XE and 7960X perform very well with the game and hit the GPU bottleneck. Rise of the Tomb Raider is really digging the cores as is Ashes of the Singularity.
In fact, Ashes of the Singularity can really take advantage of the CPU; it's a match made in heaven. The results we see here are the Skylake-X HCC parts hitting the GPU bottleneck, and while the results might be in line with Kaby Lake parts, the minimum FPS is still higher on Kaby Lake in many cases.
Overclocking and Power Consumption
CPU Overclocking
While the CPU die touches the integrated heat spreader through the same TIM as the low core count (< 10) Intel CPUs, the actual die size of a high core count (HCC) CPU is larger, meaning that the heat is spread over more surface area.
For example, a 7980XE spreads heat over more integrated heat spreader area than the 7820X, as the die is larger. That allows us to actually have a chance of cooling the die with a water cooler and overclocking. I was able to easily get up to 4.4GHz on both the 7980XE and the 7960X, but I had to use 1.2v or less VCore, while I was okay with a bit more voltage with the 7900X. Make sure to also set your VCCIN to 2.0v or higher to maintain performance.
While cooling the CPU is of one concern, another is the amount of power the CPU will consume when overclocked. We are talking about an easy 500W when going towards 4.5GHz, and that means the VRM settings, both internal to the CPU and external through the motherboard need to be expanded, and you will also need active VRM cooling.
Power Consumption
That is some intense power consumption, both at stock and overclocked.
Overclocking the CPU basically doubles the power consumption of the CPU, and you will need to take into account the motherboard's VRM, cooling, settings, and even the power supply to ensure you won't trigger multi-rail OCP protection. If you are aiming for 4.4GHz+, plan to pull 500W+ on a single 12v rail that goes to the CPU.
What's Hot, What's Not & Final Thoughts
This is where you can fast forward to the final section of the review, and get a quick recap and points on the Core i9-7980XE and 7960X.
What's Hot
Excellent Multi-Core Performance: Intel's mesh architecture seems right at home with these high core count (HCC) CPUs, and with the 16 and 18 core variants of the Skylake-X microarchitecture, we get to really see it in action and shine.
Excellent Single Core Performance: Even though multi-core performance has really improved due to the higher core count, Intel still maintains excellent single core performance, mainly due to core IPC and Turbo Boost 3.0's 4.4GHz boost.
Huge Overclocking Boost: Overclocking the 7980XE unleashes a beast, a beast that destroys anything in its path, but the gains aren't free. Just like any high performance, over the top machine, the energy required to unlock the power has to come from somewhere.
Well Rounded: Most programs are not totally single threaded or fully multi-threaded. Instead, they are a mixture of both. Programs also take advantage of a combination of per clock performance as well as frequency. The Skylake 7980XE and 7960X are well-rounded CPUs capable of doing very well in real-world environments; they do more than a few things very well.
What's Not
Power Consumption and Heat: The heat problem could be overcome more easily if thermal paste was replaced with solder between the die and heat spreader, but even then, you will need excellent cooling if you are going to overclock. The CPU also eats power when overclocked, and even at stock it still is quite high.
Cost: At $2000, the extra performance headroom will be realized by those who want the best and are willing to pay the premium for it, the cost increase doesn't scale linearly. At $1700, Intel's 16 core CPU costs $700 more than the competition, but it does offer benefits. Both the CPUs are premium products, and they are niche products, and Intel has priced them as such.
Final Thoughts
The 7980XE and 7960X are super expensive, and Intel has made them that way for a reason; they are niche products that offer more all-around performance than what is out there on the market. The best analogy I can think of is one where a 7700K is like a BMW M5 or a Tesla Model-S, Threadripper 1950X would be the Mercedes McLaren SLR, and the Skylake-X 7980XE is like the Bugatti Chiron.
The market for such a CPU is very niche, and those in that market know they are in that market. It's a CPU with advantages; it's got quick acceleration, excellent race handling, and tons of speed. It uses more of the basics to get there, with custom systems that would be counterintuitive on something lesser. Take for example the mesh, it's great on the HCC (high core count) Intel CPUs, but would be detrimental on an LCC (low core count) CPU where the ring is better.
The CPU also costs Intel more to produce, and that's because of the larger die size. A large die means fewer dies per wafer, and lower yields because the die is more likely to contain one of the many random defects that occur during production. While the CPU also costs Intel more, it will also cost you more as well.
Not only will you require a motherboard with a stronger VRM, but you will also need to invest in a strong all-in-one liquid cooler at a minimum. Power consumption is also high, and that is because performance requires energy, and the laws of thermodynamics don't allow us to just make energy without paying for it. The bottom line is that the 7980XE and 7960X are two of the fastest CPUs I have ever tested. They are the Crown Jewel of Intel's consumer lineup, and the 7980XE can perform one trillion operations per second (one Teraflop).
As with anything at the super high-end, you need to be prepared to accept its shortcomings to take advantage of its unique capabilities and supremacy.