Let’s assume that you’ve got plenty of money to spend. You’ve always wanted the best (not necessarily the fastest) desktop components money can buy. You’re the kind of individual who ventured into 4K displays when they still cost a fortune. You buy TITAN-range graphics cards and regularly pour a heap of money into your desktop setup. If you’re in this demographic, this CPU will be worthy of significant importance to you.
Of course, there are those deemed “megataskers”, who carry an equivalent level of disposable cash and may be interested in this CPU as well – but I personally don’t know anyone who would fit that classification. So the focus on the Core i9 7980XE in this case is purely from an ultra-high-end enthusiast’s perspective.
After years of dealing with small jumps in frequency, core and thread counts, AMD came along and in many ways prodded Intel into releasing a CPU that they’ve always had on hand (at least insofar as their server platforms are concerned) to the desktop market. The PC gaming crowd has always been and remains mostly concerned with single-thread performance, which is what PC titles benefit from the most.
AMD changed the course of proceedings, and we now have a CPU that exists mostly as a one-up over the competition. To that end, Intel has reclaimed the crown of having the most powerful desktop CPU money can buy. Priced at a cool R34,000, owning the Intel Core i9 7980XE means owning the most powerful desktop CPU ever created. If you’re truly interested and the price hasn’t yet deterred you, here are a few things that may interest you – things of which you should definitely be aware.
As we saw with the earlier, smaller Skylake-X CPUs, performance can be somewhat unpredictable on the X299 platform. Sometimes Skylake-X CPUs can yield lower performance than the outgoing Broadwell-E CPUs. This is partially related to the cache and mesh topology, as opposed to the ring bus / uncore scheme used on previous-generation CPUs. Essentially, this mesh topology optimizes inter-core communications, has power-saving benefits, simplifies some of the layout, and of course has better efficiency, which is what ultimately matters most. That doesn’t mean there are no drawbacks. For example, in cases where the Core i7 6950XE is faster than the equivalent Core i9 7900X, it’s partially due to these changes.
That said, it’s of little relevance to the Core i9 7980XE, simply because we’ve never had such a high-thread CPU before. Its only competition is itself and perhaps AMD’s 32-thread Threadripper 1950X, which (surprisingly) hasn’t set the enthusiast market on fire.
Given the thermal and power constraints of such a dense CPU, the Core i9 7980XE has the lowest base frequency of all CPUs within the family. All cores are guaranteed to operate at the nominal 2,600MHz under normal conditions, but as you know there are Turbo modes, specifically Turbo Boost Max 2.0 and 3.0. These both exist for improving lightly threaded operations, but needless to say Turbo 3.0 is the latest specification and it adds a couple of new features. At its most basic, Turbo Boost Max 3.0 allows the CPU to substantially ramp up the core clock of a single core. As long as there’s still some thermal and power-draw headroom, it can do this.
Using a lightly threaded application, the threads and subsequent cores which are being utilized can be made to operate significantly faster, to the tune of 4.4GHz. Again, this is for single-core operation and the operating frequency may fluctuate, because it’ll bounce around according to system conditions.
If you want to know what a realistic Turbo limit is for this CPU with all cores loaded, it’s around 4.2GHz. Turbo 3.0 takes this to the aforementioned 4.4GHz on a single core. It’ll also ensure that the task is assigned to the most capable CPU core. Furthermore, it makes sure that the CPU will, for the most part, maintain that 4.4GHz throughout the operation.
What then of the memory support? Well, if you’ve ever used any of the previous HEDT platforms, you’ll know that they’ve always had a measurably inferior memory controller compared to their performance desktop counterparts (i.e. the Z platform). Intel has remedied this and significantly improved it, so not only is there better DRAM performance via a quad-channel memory system, but frequencies as high as 4,000MHz are possible for everyday use.
These are just some of the improvements that Intel has ushered into the new Skylake-X based CPUs. If anything, these are what’ll make the most difference to your everyday performance. Cache configurations have changed and we end up with a smaller last-level cache (LLC or L3 in this case) per core than before. However, this is supposedly a better caching system that makes up for the smaller size via a restructured “smart cache”. Where those brains can’t make up for the smaller per-core cache size, the faster L2 caches have quadrupled in size. Overall, you end up with a lot more CPU cache in total.
So how does it perform then? Well, that’s easy to answer: this CPU is incredibly fast in threaded applications. There simply isn’t a CPU that comes close to what the Core i9 7980XE can do in such an environment. One thing is for sure: you’ll not be short of compute threads anytime soon. Whether it be 3D rendering, simulations, or any other highly intensive, multi-threaded, computationally heavy workload – the Core i9 7980XE makes quick work of it all. If there’s a bottleneck anywhere in your system, it certainly won’t be the CPU.
Even though this isn’t a CPU that’s specifically designed for gaming, there are those who’ll want to use it for gaming and in that respect, it’s a competent CPU. As a result of the massive power draw (which can be well over 400 watts under load, depending on the operating frequency), it may not be advisable to set a high operating frequency, purely so you can match more mainstream, high-frequency CPU performance. A recommended (or at least safer) overclock for this CPU is around 4GHz on all 18 cores. This is just about tolerable on a mid-range AIO cooler such as the Corsair H100i. Anything higher than that would require a beefier CPU cooler, and more importantly, a very capable motherboard.
You should definitely be cautious here, because when the X299 platform was introduced to vendors and they went about certifying their motherboards, Intel apparently didn’t reveal to them that there’d be high-core-count CPUs available for the platform, sporting 12 or more cores. As such, many boards feature either an inadequate VRM, or one which isn’t sufficiently cooled. When purchasing a board to match this CPU, be extra careful and make doubly sure that it explicitly supports the Core i9 7980XE. Failure to buy a compliant motherboard can result in random shutdowns, massive performance degradation and an inability to overclock at all.
On this platform, it’s very possible to set a 4.4GHz clock (for instance), but end up with lower performance than you would‘ve had at 4GHz. This is power related, and that’s why you have to ensure you buy a certified board.
With that covered, there isn’t much else of relevance to say about the Core i9 7980XE. Overclocking this CPU is of course possible, and Intel has enabled all the controls you’ll need to reach incredibly high frequencies. However, that’s only applicable if you’re using liquid nitrogen for cooling. Using an AIO (I wouldn’t recommend a regular tower air cooler for this CPU at all) means your headroom is fairly limited, as we’re dealing with a much larger core that draws a huge amount of power and outputs plenty of heat.
As an example of how much power the CPU can draw and how much heat it’s capable of putting out, it’s not unusual to see temperatures as high as 90 °C under full load on all cores using the aforementioned Corsair H100i AIO. Even under extreme conditions, using a regular high-quality KPC F1 LN2 container isn’t enough to keep the temperatures under control. Even with the container filled with liquid nitrogen at -90 °C or -100 °C, it’s possible to have the actual core temperature as high as -10 °C – or worse, 5 °C at around 5.2GHz.
Ultimately, if you’re looking at buying this CPU, consider what you’re going to use it for and the associated costs of using such a CPU. It isn’t for everyone, but for those who use the applications that can take advantage of it, it’s peerless.
R34,000 is an insane amount of money to spend on just a CPU, but for the money you get an extraordinary amount of computational power at your fingertips. By virtue of just being the most powerful CPU we’ve ever seen, it has to bag itself the Hardware award – even though its value proposition is questionable.