Synthetics and Scientific
SiSoft Sandra 2016
SiSoft Sandra gives us several very interesting data points on the Core i9-7900X. Single threaded performance is now on par with the Core i7-7700K thanks to the 4.5 GHz single-core Turbo Boost specification. That is a full 19% faster than the 6950X – a big jump for generation-to-generation increases. Multi-threaded performance is also higher, by the same 18% gap, over the 6950X.
The memory bandwidth available to the 7900X is over 55 GB/s, which is 17% faster than the 6950X even when using the same DDR4-2400 memory speed (as we are). How is that possible? It’s all a part of the new mesh CPU interconnect that Intel integrated on the Skylake-X architecture, which lowers the average latency between each core and its nearest memory controller.
Geekbench is another test that shows drastically improved single threaded performance on the Core i9-7900X CPU, jumping by 22% over the 6950X 10-core CPU and coming within a reasonable step of the 7700K. The multi-threaded performance only increases by 5% though, which is much lower than anticipated.
Though the single-threaded performance in this test shows the 7900X is well behind the 7700K, the pure ability of the 10-core/20-thread design races past once we saturate four threads. There is not the same kind of performance jump from the 6950X to the 7900X that we would expect though, telling us that maybe this workload is showing some sensitivity to the higher LLC cache latencies we demonstrated on an earlier page.