Best Eight-Core CPU Battle: AMD Ryzen 7 3800X vs Intel Core i7-9700K

(Image credit: Shutterstock)

The number of cores on a processor is very important. At the end of the day, the cores, combined with frequency and architecture, dictate the amount of performance the chip can deliver. However, while having more of anything is typically better, not everyone needs a ton of cores or can put them to good use. Times have changed, and now it's common to find mainstream processors with up to 16 cores, such as the AMD Ryzen 9 3950X, but that healthy ration of cores, and the higher price point, isn't for everyone.

Assuming that you're looking for an octa-core chip, there are two formidable offerings on the market.

The Ryzen 7 3800X, codename Matisse, represents Team AMD. The processor is equipped with eight cores and 16 threads. On the other hand, we have the Core i7-9700K (codename Coffee Lake) chip, Intel's first Core i7 part that lacks Hyper-Threading technology. As a result, the Core i7-9700K checks in with eight cores and eight threads. The reason why we pick the Core i7-9700K for over the Core i9-9900K for this comparison is because the price tag on the former is the closest to the Ryzen 7 3800X.

To help you pick one, we put the octa-core processors from both chipmakers through a seven-round face-off, based on their features, overclocking, coolers, motherboards, performance, and value. If you're looking for a processor in a different price band, be sure to check out our Best CPUs page.

Features

AMD taps into TSMC's 7nm FinFET manufacturing process for the Ryzen 7 3800X. The eight-core, 16-thread chip leverages the latest Zen 2 microarchitecture and packs 32MB of L3 cache. The octa-core chip ticks along with a 3.9 GHz base clock and a 4.5 GHz single-core boost clock.

Like AMD's other Zen 2 products, the Ryzen 7 3800X arrives with native support for DDR4-3200 memory modules. The processor provides users with up to 16 speedy PCIe 4.0 lanes to take advantage of the latest SSDs and graphics cards, but it lacks integrated graphics.

Swipe to scroll horizontally
Header Cell - Column 0 Intel Core i7-9700KAMD Ryzen 7 3800X
ArchitectureCoffee LakeZen 2
SocketLGA1151AM4
Cores / Threads8 / 88 / 16
Base Frequency (GHz)3.63.9
Boost Frequency (GHz)4.94.5
L3 Cache12MB32MB
Process14nm7nm
TDP95W105W
Memory SpeedDDR4-2666DDR4-3200
Memory ControllerDual-ChannelDual-Channel
Integrated GraphicsIntel UHD Graphics 630N/A
Recommended Customer Pricing$374 - $385$399

The Core i7-9700K is still on Intel's 14nm process node and Coffee Lake microarchitecture. Unlike the Ryzen 7 3800X, the Core i7-9700K is limited to eight cores and eight threads. Intel bestows the octa-core processor with 12MB of L3 cache and base and single-core boost clock speeds up to 3.6 GHz and 4.8 GHz, respectively.

The Core i7-9700K has a dual-channel memory controller that officially maxes out at 128GB. However, the Ryzen 7 3800X is a step ahead of the Core i7-9700K in terms of memory speed support. The Ryzen 7 3800X plays fine with DDR4-3200 memory out of the box while Intel guarantees the Core i7-9700K up to DDR4-2933. The Core i7-9700K also comes equipped with Intel's integrated UHD Graphics 630 graphics solution.

Winner: AMD. The Ryzen 7 3800X has twice the thread count of the Core i7-9700K. The AMD chip also comes with 166% more L3 cache, which comes in handy for workloads that are sensitive to cache capacity. It1s other strong attributes include support for PCIe 4.0 and the DDR4-3200 standard. In Intel's case, the Core i7-9700K does come with integrated graphics, a must if you don't have a discrete graphics card, but that alone isn't enough to warrant a win over the Ryzen 7 3800X.

Motherboard Options

(Image credit: Tom's Hardware)

The Ryzen 7 3800X supports AMD's long-lived AM4 socket that resides on AMD 300-, 400-and 500-series motherboards. It's true that the only way to enjoy the benefits of the PCIe 4.0 interface is with the a newer 500-series motherboard, but there are still a plethora of options to choose from if you don't need the faster transfer speeds. In terms of pricing, the cheapest compatible motherboard for the Ryzen 7 3800X is available for $55, while the most affordable X570-based motherboard starts at $145.

The Core i7-9700K snaps into the LGA1151 socket as long as it is built around Intel's 300-series chipset. Although the LGA1151 has provided housing for two previous generations of chipsets, Coffee Lake processors aren't backward compatible with prior chipsets. In terms of pricing, budget Intel 300-series motherboards sell for as low as $55, while Z370 and Z390 models start at $115.

Coffee Lake is likely the last generation of processors that will grace the LGA1151 socket. Intel is expected to introduce the new LGA1200 socket for its upcoming Comet Lake chips. This means that those buying a LGA1151 motherboard today are basically investing in a moribund platform.

On the contrary, AMD, which has always provided better inter-generational support, has committed to the AM4 socket until 2020. Therefore, the next-generation Ryzen 4000-series parts are rumored to slide into the AM4 socket. Barring any significant changes, the new processors should be backward compatible with 500-series motherboards.

Winner: AMD. Both platforms offer a wide range of options for consumers. There are inexpensive models that cost almost nothing, and impeccably engineered models that command eye-watering prices. Nevertheless, if the rumors are true, the AM4 platform still has one last breath.

Overclocking Potential

Both the Ryzen 7 3800X and Core i7-9700K come with unlocked multipliers that enable support for manual overclocking. Notwithstanding, Intel continues to have the upper hand in overclocking.

AMD has affirmed in the past that the chipmaker maximizes its Ryzen 3000-series processor for the best performance right out of the box. That's a clever way of saying that the Zen 2 chips don't have much manual overclocking headroom, but that's because the company exposes nearly the full performance of the processors at its stock settings. 

While AMD advertises the Ryzen 7 3800X with a 4.5 GHz boost clock, the chip only hits that frequency on a single physical core, and like we see with most boost algorithms, under very specific conditions. Our experience with the Ryzen 7 3800X confirms AMD's statements. We could only get our Ryzen 7 3800X sample stable at 4.3 GHz on all cores with a 1.42V Vcore and an Auto Load-Line Calibration (LLC) setting.

Intel markets the Core i7-9700K with a 4.9 GHz boost clock, which is also the boost for a single core as well, although it can hit this frequency on any given core. The all-core boost for this model is 4.6 GHz. It's important to mention that, unlike previous processors, the Core i7-9700K uses a solder-based thermal interface material (STIM). In theory, this helps with heat transfer and increases headroom for overclocking. Our Core i7-9700K sample could sustain a 5.1 GHz overclock across all eight cores with a 1.345V Vcore and the LLC setting on automatic.

Winner: Intel. AMD's Zen 2 microarchitecture and TSMC's 7nm FinFET manufacturing process are still in diapers compared to Intel's incessantly-optimized 14nm node, so it's not surprising that that the first Zen 2 chips have little manual overclocking headroom. The Core i7-9700K is simply superior for manual overclocking.

Cooling Solutions

(Image credit: AMD)

Neither the Ryzen 7 3800X or Core i7-9700K are space heaters. You can get by with moden aftermarket cooling solutions of either the air or liquid variety. 

The Ryzen 7 3800X has an official TDP (thermal design power) rating of 105W. If you already own an AM4 motherboard and are upgrading to the Ryzen 7 3800X, you can reuse the same CPU cooler as long as its cooling capacity meets the Ryzen 7 3800X's requirement. In any event, AMD includes the capable Wraith Prism cooler with the Ryzen 7 3800X.

The Core i7-9700K comes with a 95W TDP, apparently 10W less than the Ryzen 7 3800X, but these companies measure TDP based on entirely different criteria. The TDP value on Intel processors can be a bit misleading as the number represents the power consumption at the base clock speed. Once the chip's boost clock kicks in, the actual power consumption is a lot higher. In our review, the Core i7-9700K pulled up to 200W when pushed to the limit.

Winner: AMD. At peak loads, the Ryzen 7 3800X draws significantly less power in comparison to the Core i7-9700K. Consequently, its cooling requirements aren't as steep as the Core i7-9700K. Unlike Intel, AMD continues to bundles its stock coolers even with its high-end SKUs. Unless you're overclocking to the edge, the Wraith Prism will serve you well. 

Intel doesn't include a stock cooler with the Core i7-9700K, which forces consumers to spend extra cash on an aftermarket cooling solution even if they don't plan on overclocking.

Gaming Performance

The Core i7-9700K and Ryzen 7 3800X aren't specifically aimed at gamers only. However, streamers and gaming content creators could find some very good value in the aforementioned octa-core chips due to their generous core counts.

The gaming results are in Intel's favor. Whether it be a big or negligible difference, the Core i7-9700K beats the Ryzen 7 3800X in all our gaming tests.

Winner: Intel. Hands down, the Core i7-9700K is the better gaming processor overall. If you use your processor primarily for gaming, the Core i7-9700K is a good choice.

Productivity Performance

The Ryzen 7 3800X might fall behind the Core i7-9700K in gaming, but it excels in other areas where having more cores is an advantage. 

Thanks to its SMT (Simultaneous multithreading) capability, the Ryzen 7 3800X beats the Core i7-9700K in just about every multi-core workload, including general productivity, rendering, encoding and compression.

Winner: AMD. The Ryzen 7 3800X's multi-core performance is an absolute force to reckon with. The Core i7-9700K's lack of HyperThreading is exposed in workloads that reward more cores. However, the Core i7-9700K holds its own in single-core workloads. 

Value Proposition

Swipe to scroll horizontally
Header Cell - Column 0 Price Per CoreCurrent Pricing (USD)Cores / ThreadsTDP (Watts)Base / Boost Frequency (GHz)L3 Cache (MB)PCIe Lanes
Core i9-9900K$65.62$524.998 / 16953.6 / 5.01616 x PCIe 3.0
Core i7-9700K$46.25$369.998 / 8953.6 / 4.91216 x PCIe 3.0
Ryzen 7 3800X$42.50$339.998 / 161053.9 / 4.53216 x PCIe 4.0
Ryzen 7 3700X$38.61$308.898 / 16653.6 / 4.43216 x PCIe 4.0

The Ryzen 7 3800X currently sells for $339.99, which works out to $42.50 per core. Meanwhile, the Core i7-9700K costs $369.99, or $46.25 for each core. On a pure price-to-price comparison, the Ryzen 7 3800X results in a better deal.

Since the Ryzen 7 3800X comes with a stock cooler, you only need to buy an AM4 motherboard if you don't own one. The big problem is that AMD doesn't have any motherboards outside of the X570 stack that support PCIe 4.0. The X570-based motherboards significantly increases the overall cost: You'll spend between $145 to $700 for a motherboard.

Rolling with the Core i7-9700K implies investing not only in a motherboard but also an aftermarket CPU cooler. Although you can get away with pairing the chip with a low-end 300-series motherboard, you probably want to shell out for a Z370 or Z390 motherboard for their added features. Z370 offerings retail for roughly $115 and $470, while Z390 retails between $115 and $965. A half-decent cooler to keep the Core i7-9700K's temperatures in check will set you back another $30, at the very least.

Winner: AMD. In general, it's slightly cheaper to put together a system around the Ryzen 7 3800X. Once AMD and its motherboard partners releases more affordable 500-series products, you'll get more bang for your buck.

The Bottom Line

If you're looking for a chip that can chew through a wide range of both threaded workloads and still handle gaming adeptly, Ryzen 7 3800X is the better pick of the two. AMD's octa-core offers cutting-edge features, like PCIe 4.0 support, and delivers exceptional performance in multi-core workloads. If you're looking for a processor for work, the Ryzen 7 3800X is hard to pass by. Ultimately, the Ryzen 7 3800X's biggest competitor comes from within AMD's own stable: The Ryzen 7 3700X is a very capable processor that brings the lion's share of the 3800X's performance, but at a lower price point. Keep that in mind at checkout. 

The Core i7-9700K has two things going for it: The processor really shines in gaming and is a fun to overclock. We don't expect anyone to pick up a Core i7-9700K just to play games, so gaming performance ultimately takes the backseat. At stock settings, the Core i7-9700K is not even close to catching the Ryzen 7 3800X in multi-core workloads. The chip, when overclocked to 5.1 GHz, closes the performance gap in some situations. However, neither we or Intel can guarantee that every sample can hit that frequency.

Meanwhile, if you're looking for more general recommendations, check out our guide on how to buy a CPU.  

Overall Winner: AMD

Swipe to scroll horizontally
Round Intel Core i7-9700KAMD Ryzen 7 3800X
FeaturesRow 0 - Cell 1
Motherboard OptionsRow 1 - Cell 1
Overclocking PotentialRow 2 - Cell 2
Cooling SolutionsRow 3 - Cell 1
GamingRow 4 - Cell 2
Productivity PerformanceRow 5 - Cell 1
Value PropositionRow 6 - Cell 1
Total25

MORE: Best CPUs

MORE: Intel & AMD Processor Hierarchy

MORE: All CPUs Content

Test System and Configuration

Swipe to scroll horizontally
AMD Socket AM4 (X570)AMD Ryzen 9 3900X, Ryzen 7 3800X, Ryzen 7 3700X, Ryzen 5 3600X, Ryzen 7 2700X
Row 0 - Cell 0 MSI MEG X570 Godlike
Row 1 - Cell 0 2x 8GB G.Skill Flare DDR4-3200Ryzen 3000 - DDR4-3200, DDR4-3600
Row 2 - Cell 0 Second-gen Ryzen - DDR4-2933, DDR4-3466
Intel LGA 1151 (Z390)Intel Core i9-9900K, i7-9700K, Core i5-9600K
Row 4 - Cell 0 MSI MEG Z390 Godlike
Row 5 - Cell 0 2x 8GB G.Skill FlareX DDR4-3200 @ DDR4-2667 & DDR4-3466
AMD Socket AM4 (X470)AMD Ryzen 5 1600X
Row 7 - Cell 0 MSI X470 Gaming M7 AC
Row 8 - Cell 0 2x 8GB G.Skill FlareX DDR4-3200 @ DDR4-2933
All SystemsNvidia GeForce RTX 2080 Ti 
Row 10 - Cell 0 2TB Intel DC4510 SSD
Row 11 - Cell 0 EVGA Supernova 1600 T2, 1600W
Row 12 - Cell 0 Windows 10 Pro (1903 - All Updates)
CoolingCorsair H115i - Stock and OC cooler except where noted in charts
Row 14 - Cell 0 Custom Loop, EKWB Supremacy EVO waterblock, Dual-720mm radiators (HEDT only - n/a here)
Row 15 - Cell 0 AMD Wraith Spire, as noted
Zhiye Liu
RAM Reviewer and News Editor

Zhiye Liu is a Freelance News Writer at Tom’s Hardware US. Although he loves everything that’s hardware, he has a soft spot for CPUs, GPUs, and RAM.

  • Evil_Overlord
    I find it very interesting that despite the 3800X having more L3 Cache, faster memory speeds, and hyperthreading, the 9700K beats it in all gaming benchmarks. Thanks for the article.
    Reply
  • joeblowsmynose
    Evil_Overlord said:
    I find it very interesting that despite the 3800X having more L3 Cache, faster memory speeds, and hyperthreading, the 9700K beats it in all gaming benchmarks. Thanks for the article.

    Right? Because "hyperthreading" makes games run waaay faster and clock speeds don't have any impact ... :P

    SMT won't really improve game performance and games love high clocks - its straight forward.
    Reply
  • GoatGuy
    Evil_Overlord said:
    I find it very interesting that despite the 3800X having more L3 Cache, faster memory speeds, and hyperthreading, the 9700K beats it in all gaming benchmarks. Thanks for the article.
    Gaming drivers ARE optimized for the Intel line, because all competent programming teams figure "our largest market historically has been for Intel processors". It takes Ryzen specialization to optimize drivers (and installtion-self-modification-options) for them.
    Reply
  • cwolf78
    The reason why Intel still holds a slight advantage in gaming is inter-core latency. Intel, which are still using monolothic dies with a ring bus architecture, have lower inter-core latency compared to AMD's CCX and chiplet architecture. AMD keeps making strides in reducing this latency each generation with upgrades to their Infinity Fabric and by using large amounts of L3 cache. Intel is going to be using a similar approach to their chip design when they reach 7 nm and they will go through the same teething issues as AMD. (Rumors currently are that Intel are having a lot of difficulty getting their fabric's power consumption under control.) This combined with the projected performance increase with Zen 3 leads me to believe there will no longer be any difference in gaming performance between the two with perhaps a slight edge for AMD. And the best part is, if you're a current AMD customer, you can upgrade to Ryzen 4000 (Zen 3) on your current platform.
    Reply
  • Redneck5439
    joeblowsmynose said:
    Right? Because "hyperthreading" makes games run waaay faster and clock speeds don't have any impact ... :p

    SMT won't really improve game performance and games love high clocks - its straight forward.

    Agree totally with you. Hyperthreading in games is basically pointless, frequency is much more important (at least in the current generation with their current IPC). Even today's "modern" games that take advantage of more cores / threads don't typically leverage more than 6 cores in a meaningful manner and will rarely take advantage of all 8 cores. I have found that I get better gaming performance with my 3800X if I disable SMT and increase the overclock for this very reason. With SMT on my max overclock is 4.5Ghz all core @ 1.41V, with SMT off my max overclock is 4.575Ghz all core @ 1.41V. The gaming performance is better with 8 cores 8 threads @ 4.575Ghz than running with stock boost or with running 8 cores 16 threads @ 1.5Ghz.
    Reply
  • Redneck5439
    cwolf78 said:
    The reason why Intel still holds a slight advantage in gaming is inter-core latency. Intel, which are still using monolothic dies with a ring bus architecture, have lower inter-core latency compared to AMD's CCX and chiplet architecture. AMD keeps making strides in reducing this latency each generation with upgrades to their Infinity Fabric and by using large amounts of L3 cache. Intel is going to be using a similar approach to their chip design when they reach 7 nm and they will go through the same teething issues as AMD. (Rumors currently are that Intel are having a lot of difficulty getting their fabric's power consumption under control.) This combined with the projected performance increase with Zen 3 leads me to believe there will no longer be any difference in gaming performance between the two with perhaps a slight edge for AMD. And the best part is, if you're a current AMD customer, you can upgrade to Ryzen 4000 (Zen 3) on your current platform.

    This and the fact that Intel's upcoming 10nm can't support the clock speeds of its current 14nm+++(+?) is why Intel has held off so long with bring 10nm to market. I believe that Intel is already looking at chiplet design after the success that AMD has had and when they bring high performance desktop 10nm it will feature the chiplet design. Intel is already struggling to keep up with AMD in core count and needs to adapt a chiplet design to be able to do so. However the increased latency (of a chiplet design) paired with lower frequency (of 10nm) is exactly why Intel doesn't have high end desktop 10nm processors already on the market or coming to market this year. Their 10nm high core count desktop processors while being much more efficient (and much more competitive with productivity work loads) would loose the one edge that Intel can still boast about - gaming performance. With higher latency and lower clock speeds they wouldn't be able to compete against their current i9 9900K(S) in performance and marketing its better efficiency would be a very hard sell. That is why we see Intel releasing a 10 core 14nm+++(I really don't know how many pluses we are up to now) rather than finally releasing 10nm (desktop).
    Reply
  • Gurg
    The unbiased Bottom Line take away should be that if you want top performance in gaming (13.5% higher FPS) and Office ( 4.6% better) buy Intel. If you primarily are into quicker performance in video editing, rendering etc buy AMD.

    If you are swayed by the inclusion of a $30 CPU air cooler in the purchase price, then you have way more issues that a $300-400 CPU won't help.

    Note: article uses charts from seven month old 3600x review.
    Reply
  • Redneck5439
    Really at this point if you are considering building a new rig you should really hold off for a few more months. Intel is getting the next gen ready for launch right now headed up by the 10900K with 10 cores and 20 threads. By June or July at the latest we will have AMD releasing their Zen 3 Ryzen 4000 series processors. I don't know if Intel can leverage anymore IPC out of their 14nm process or if the 10900K will just be a 9900K with 2 more cores, but AMD is claiming a 15% - 17% IPC increase with Zen 3. Several years ago I would have said its all hype, but AMD has delivered on its IPC claims since they released fist gen Ryzen.

    If AMD really does have 15 - 17% IPC increases coming with Zen 3 then they will have the most dominant processors available in any segment (gaming, editing, rendering, anything) by the end of the year. A 10900K with 10 cores, 20 threads and boost clock of 5.2Ghz is impressive but won't be able to save Intel if you compare it to a 3900X with 15 - 17% better performance across the board, which is what the 4900X should be all things being equal.

    Now, will this happen? Will AMD finally have a totally dominant processor lineup with Zen 3? I don't know, and neither does anyone else. I don't have a crystal ball and Intel may indeed have something more up their sleeve than just a highly binned 9900K with 2 extra cores. The point is the 10900K should be releasing in a couple months and Zen 3 will be releasing very soon thereafter. If you are planning a new build you may just want to see what they have to offer before building now. At the very least the release of the new processors should drive the costs of existing processors down in just a few months time.
    Reply
  • 2Be_or_Not2Be
    Gurg said:
    The unbiased Bottom Line take away should be that if you want top performance in gaming (13.5% higher FPS) and Office ( 4.6% better) buy Intel. If you primarily are into quicker performance in video editing, rendering etc buy AMD.

    If you are swayed by the inclusion of a $30 CPU air cooler in the purchase price, then you have way more issues that a $300-400 CPU won't help.

    According to the Amazon links, it's $399 for the 9700K and $339 for the 3800X. That price differential, plus the $30 for the fan, makes it almost a $100 difference. That's a sizable difference; $100 more can almost buy you the motherboard to run that new CPU. You shouldn't so easily diminish the value of that $30 cooler.
    Reply
  • sizzling
    The Ryzen 7 3700X is a very capable processor that brings the lion's share of the 3800X's performance, but at a lower price point. Keep that in mind at checkout.

    Now that’s an understatement. Just had a quick look and the 3700X is about 14% cheaper in the UK while giving nearly identical performance to the 3800X. They perform so closely you have to ask why they both exist and the only answer I can come up with is marketing and squeezing a bit more out of customers who don’t properly research their next purchase.
    Reply