Amidst announcements of decreased PC sales, large cuts to its workforce and the discontinuation of its mobile Atom processor line, Intel quietly released three new CPUs sporting the Skylake-H architecture. The new processors feature Intel Iris Pro Graphics and an improved 2nd generation cache architecture with 128 MB eDRAM onboard referred to as “Crystal Well.”
|Processor||Intel Core i5-6585R||Intel Core i5-6685R||Intel Core i7-6785R|
|L3 Cache||6 MB||6 MB||8 MB|
|Base Clock Frequency||2.8 GHz||3.2 GHz||3.3 GHz|
|Max Turbo Frequency||3.6 GHz||3.8 GHz||3.9 GHz|
|TDP||65 Watt||65 Watt||65 Watt|
|Memory Type||Dual ChannelDDR4- 1866/2133DDR3L- 1333/1600 @ 1.35 V||Dual ChannelDDR4- 1866/2133DDR3L- 1333/1600 @ 1.35 V||Dual ChannelDDR4- 1866/2133DDR3L- 1333/1600 @ 1.35 V|
|Memory Bandwidth||34.1 GB/s||34.1 GB/s||34.1 GB/s|
|Max Memory Capacity||64 GB||64 GB||64 GB|
|Graphics Engine||Intel Iris Pro Graphics 580||Intel Iris Pro Graphics 580||Intel Iris Pro Graphics 580|
|Graphics Base Clock||350 MHz||350 MHz||350 MHz|
|Graphics Max Dynamic Frequency||1.1 GHz||1.15 GHz||1.15 GHz|
The Intel Core i5-6585R, i5-6685R and i7-6785R can be soldered into the current BGA 1440 socket, which often finds a home in small form factor (SFF) or all-in-one (AIO) PCs with a 65-watt TDP. Intel was able to improve the cache size compared to the previous Broadwell-based 65-watt processors, giving the Skylake-R chips the same cache size as their desktop counterparts, albeit with a slightly lower clock rate.
The codename “Crystal Well” refers to the added eDRAM cache, which in previous implementations acted as a victim cache for the L3 cache by adding up evicted cache lines from the L3 for quick re-reading, circumventing the main memory. This was particularly useful for gaming and graphics performance where textures are re-read from the memory frequently. However, the data could not exist in the eDRAM without first being accessed, giving initial read latencies the same performance as previous processors.
The 2nd generation Crystal Well cache inside these new Skylake-R processors places the eDRAM in a different segment of the data chain, between the System Agent and the DDR memory. This makes the eDRAM act more like a DRAM buffer, with 50 GB/s bandwidth available in each direction to the LLC. The eDRAM is also accessible for early read and writes by any device that accesses memory via the system agent, including anything running through the PCIe lanes (which was not possible prior to these new processors).
Intel Iris Pro Graphics 580 should add significant graphics horsepower to the package, but with full specifications of the iGPU not yet available, it is hard to nail down a concrete analysis. However, it should provide a noticeable bump in performance compared to previous generations thanks to the improved 128 MB eDRAM cache.
The new Intel Skylake-R processors are available now, and OEMs and system builders should start implementing the new chips in AIOs, SFFs and other devices in the next few months. The new CPUs received far less fanfare than the initial Skylake launch, and it could be indicative of a sullen demeanor within Intel due to a recent string of disappointing announcements. However, new Skylake processors with Iris Pro graphics and 128 MB of eDRAM seem like a pretty big deal to us.