Announced at Computex 2017, the new Intel Core X-series processor family for desktops, are available now for pre-order and will begin shipping to consumers on June 26. This is the first set - five of the nine total SKUs - to roll out in this new family of processors.
The SKUs available for pre-order are: Intel Core i5-7640X X-series processor (MSRP: $242), Intel Core i7-7740X X-series processor (MSRP: $339), Intel Core i7-7800X X-series processor (MSRP: $389), Intel Core i7-7820X X-series processor (MSRP: $599) and Intel Core i9-7900X X-series processor (MSRP: $999).
The 12-core processor is expected to start shipping in August and 14- to 18-core processors are expected to start shipping in October.
| |
Core i7-7800X |
Core i7-7820X |
Core i9-7900X |
| Cores / Threads |
6/12 |
8/16 |
10/20 |
| Base Clock |
3.5 GHz |
3.6 GHz |
3.3 GHz |
| Turbo Clock |
4.0 GHz |
4.3 GHz |
4.3 GHz |
| TurboMax Clock |
N/A |
4.5 GHz |
4.5 GHz |
| L3 |
8.25 MB |
11 MB |
13.75 MB |
| PCIe Lanes |
28 |
44 |
| Memory Channels |
4 |
| Memory Freq |
DDR4-2400 |
DDR4-2666 |
| TDP |
140W |
| Price |
$389 |
$599 |
$999 |
The Core i9-7900X is the 10-core processor and set to have a tray price of $999, which means the shelf price will be around $1049-$1099. The Core i9-7900X is also the only one with a full complement of 44 PCIe lanes from the processor. In terms of specifications Intel is supporting a maximum turbo frequency of 4.3 GHz, or up to 4.5 GHz with the core mode. The base frequency is lower than the other CPUs to compensate, at 3.3 GHz. This all comes in a 140W TDP, with support up to DDR4-2666 in quad channel mode at 1 DIMM per channel (DDR4-2400 at 2DPC).
The Core i7-7820X sits below, exchanging two of the CPU cores and some PCIe lanes for a higher base frequency. This is an eight-core part, which reduces the total cache as well, but has a base frequency of 3.6 GHz to compensate. The PCIe lanes are reduced from 44 to 28, although Intel notes this is still enough for a single GPU and three PCIe 3.0 x4 devices directly attached to the processor. DRAM support is the same as the Core i9 at DDR4-2666, as is also the TDP at 140W.
The bottom processor is the Core i7-7800X, with six cores, a lower frequency (3.5 GHz base, 4.0 GHz turbo, no favored core support), 28 PCIe lanes, and support only up to DDR4-2400.
The processors are compatible with the new X299-based motherboards (LGA2066).
Skylake-X brings a few changes. The biggest microarchitecture change comes in three stages: the addition of an AVX-512 unit, the adjustment in the L2/L3 cache structure, and the transition to a mesh-based topology.
AVX-512 should allow compilers to vectorize more elements of regular code bases and achieve acceleration, but for the most part it is still an enterprise feature with a focus on cryptography, compute, and the financial services industry.
The L2/L3 cache arrangement adjustments are moving from a 256KB/core L2 cache to a 1MB/core L2 cache with a slightly higher latency should help with data streams being fed into the core, especially for heavy compute workloads and keeping those AVX512 units fed. However, the L3 cache being demoted to a 1.375MB/core non-inclusive victim cache, which will have limited functionality on a number of workloads, most notably compile tests.
The new mesh topology for the Skylake-SP core is not entirely new, since Intel has applied mesh architectures with the Xeon Phi chips. Typically, ore-to-core latency will vary based on the locality of the cores, and those nearest the DRAM controllers will get the best benefit for memory accesses.
Both the 12-core Core i9-7920X and AMD's ThreadRipper parts are set to launch this summer.
According to the first reviews that havebeen published online, the new Core i9-7900X is the fastest consumer CPU ever produced by Intel. The problem is, however, that at $1,000 for a 10-core chip, you're paying about 100 percent over an 8-core Ryzen 7 chip for about 30 percent more performance.