Intel Finalizes Skylake-X Processor Specifications: 18-Cores, 4.4 GHz Turbo, 165W on September 25thby Ian Cutress on August 7, 2017 12:34 PM EST
When Intel launched its new high-end desktop platform a few weeks ago, we were provided with Core-X CPUs from quad cores on the latest Kaby Lake microarchitecture, and 6/8/10 core parts on the Skylake-SP microarchitecture derived from the enterprise line and taking a different route to how the cache was structured over Skylake-S. At the time we were told that these latter parts would be joined by bigger SKUs all the way up to 18 cores, and up to $2000. Aside from core-counts and price, Intel was tight lipped on the CPU specifications until today.
Skylake-X goes HCC
The original Skylake-X processors up to 10 cores used Intel’s LCC silicon, one of the three silicon designs typically employed in the enterprise space, and the lowest core count. The other two silicon designs, HCC and XCC, have historically been reserved for server CPUs and big money – if you wanted all the cores, you had to pay for them. So the fact that Intel is introducing HCC silicon into the consumer desktop market is a change in strategy, which many analysts say is due to AMD’s decision to bring their 16-core silicon into the market.
Both the new HCC-based processors and the recently released LCC-based processors will share the same LGA2066 socket as used on X299 motherboards, and all the processors will differ in core count, with slight variations on core frequencies, TDP and price.
The Skylake-X line-up now looks like:
|Cores / Threads||6/12||8/16||10/20||12/24||14/28||16/32||18/36|
|Base Clock / GHz||3.5||3.6||3.3||2.9||3.1||2.8||2.6|
|Turbo Clock / GHz||4.0||4.3||4.3||4.3||4.3||4.3||4.2|
|L3||1.375 MB/core||1.375 MB/core|
|Memory Freq DDR4||2400||2666||2666|
Along with this, we have several release dates to mention.
- The 12-core Core i9-7920X will be available from August 28th
- The 14-18 core parts will be available from September 25th (my birthday…)
On the specification side, the higher-end CPUs get a kick up in TDP to 165W to account for more cores and the frequency that these CPUs are running at. The top Core i9-7980XE SKU will have a base frequency of 2.6 GHz but a turbo of 4.2 GHz, and a Favored Core of 4.4 GHz. The turbo will be limited to 2 cores of load, however Intel has not listed the ‘all-core turbo’ frequencies which are often above the base frequencies, nor the AVX frequencies here. It will be interesting to see how much power the top SKU will draw.
One question over the launch of these SKUs was regarding how much they would impinge into Intel’s Xeon line of processors. We had already earmarked the Xeon Gold 6154/6150 as possible contenders for the high-end CPU, and taking the price out of the comparison, they can be quite evenly matched (the Xeons have a lower turbo, but higher base frequency). The Xeons also come with multi-socket support and more DRAM channels, at +60% the cost.
Comparing against AMD’s Threadripper gives the following:
|Cores/Threads||18 / 36||16 / 32||16 / 32|
|Base/Turbo||2.6 / 4.2 / 4.4||2.8 / 4.2 / 4.4||3.4 / 4.0|
|GPU PCIe 3.0||44||44||60|
|L2 Cache||1 MB/core||1 MB/core||512 KB/core|
|L3 Cache||24.75 MB||22.00 MB||32.00 MB|
We fully expect the review embargoes to be on the launch dates for each CPU. Time to start ringing around to see if my sample was lost in the post.
- The Intel Skylake-X Review: Core i9 7900X, i7 7820X and i7 7800X Tested
- The Intel Kaby Lake-X i7 7740X and i5 7640X Review
- The Intel Core i7-7700K (91W) Review
- The Intel Core i5-7600K (91W) Review: The More Amenable Mainstream Performer
- The Intel Core i3-7350K (60W) Review: Almost a Core i7-2600K
Update on 8/8:
Due to some sleuthing, PCGamer managed to obtain turbo frequencies based on per-core loading. I'm surprised Intel doesn't give this data out like candy when the products are announced, but we're glad to have it nonetheless.
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ddriver - Monday, August 7, 2017 - linkI meant "which will not translate in MORE than 13% performance increase"
Drumsticks - Tuesday, August 8, 2017 - linkJust saying, Intel mentioned that the stock 16 core scores 3200 on Cinebench. That's about 7%+ better than TR 16C. Maybe overclocking Threadripper could put it even. The 18 core is going to be faster than "on par or slightly below" TR.
ddriver - Tuesday, August 8, 2017 - linkWhere did they mention it? In a dream of yours? Got a source? Because this sounds quite implausible.
mkaibear - Tuesday, August 8, 2017 - linkReally ddriver? Can't be bothered to even google for "7960X cinebench"?
ddriver - Tuesday, August 8, 2017 - linkDunno honestly, it is an intel tweet that directs to an engaged article that claims that intel claimed that score.
But even if true, TR would still be a WHOOPING 85% better value. So... kind of a moot point.
tamalero - Tuesday, August 8, 2017 - linkSounds like an echo chamber technique to try way too hard to look real.
tamalero - Tuesday, August 8, 2017 - linkNevermind, the whole article looks like a paid PR announcement by Intel.
silverblue - Tuesday, August 8, 2017 - linkThe 7980X appears to have lower clocks than the 7960X (2.6 vs. 2.8). They all have a 4.4GHz max turbo speed. IPC, at least as concerns floating point work, appears to be with Intel, but power consumption is going to be very interesting.
Drumsticks - Tuesday, August 8, 2017 - linkHahahahaha okay.
Someone's already linked the tweet. You really think @intelnews is going to tweet something that will EASILY be disproved wildly false? Sure, I'll grant, it's easy to mislead people, but you're reaching if you think its going to end up scoring 2k and they'll be like "Oops sorry, we meant 3200 in Octal!"
Skylake-X is going to outperform threadripper. Unless something wildly strange happens, that's an easy conclusion to make. 8 Core Skylake-X is notably faster than the 1800X after all. All of the lakes are notably faster, core for core, than Ryzen.
You do have it right that TR offers quite a good value. It's going to draw enthusiasts and new enthusiasts to AMD's platform for sure; enthusiasts are used to paying up to $1k for good CPUs. But there are a lot of businesses who will be happy to pay for the higher performance if they need it, and Skylake-X will probably continue to sell well.
ddriver - Tuesday, August 8, 2017 - link"8 Core Skylake-X is notably faster than the 1800X after all. "
That's a rather short-sighted way to look at it. Because you fail to account to account for one CRUCIALLY IMPORTANT thing - TDP budget.
Granted, both 1800x have 8 cores, and the same 3.6 GHz base clock, and intel has a slight IPC advantage, allowing the 7820X to score above the 1800x, but the advantage is the rather modest 6.7%.
But the 7820X required the rather significant 60 % of power to beat the 1800x by the measly 6.7%.
Granted, the HCC parts will be significantly lower clocked in order to get better performance per watt, but they will still be ultimately limited by TDP.
TR is quite literally two ryzens, there is only 200 MHz clock difference between ryzen and TR. And there is an entire GIGAHERTZ between the 8 core and 18 core skylake x.
So no, it is not as simple as "if the 8 core intel is faster than the 8 core zen, then the 16 core intel will be faster than the 18 core zen".
If that score intel are showing off is indeed true, then it is a product of the turbo, and understandable, as the CB test lasts for like several seconds, so it is not likely to run into any problems.
But prosumer workloads are rarely limited to bursts of several seconds. On the contrary, many of those systems will likely crunch data for hours. Which is where intel's lousy power and thermal performance will reveal itself.
And if anything, intel's HCC chips will actually be even less power efficient, because they have additional core circuitry.
Intel has had a long history of dirty tricks for when it cannot out-compete with performance, and they are back to it since zen arrived. Their goal is to discourage as many people as possible from buying TR now, as it will launch in just 2 days.
And for better or worse, intel's "superior" products won't be available for significantly longer than this, so it will take a while before they can be called on their BS by putting actual products to actual, practical work.
At 8 cores, intel has over 50% lower performance per watt, and even if we are extremely generous towards intel and assume that down-clocking will be able to win them a 30% improvement in that figure, it is still mathematically impossible for them to beat a 180W TR with a 165W SX.
It would take at the very least a 220 watt TDP for skylake X to beat 180 watts of zen. Which means that the number they claimed for the "stock" 16 core SX is actually achieved by means of OVERCLOCK that will MOST DEFINITELY not be possible to sustain for extended periods of time.