Semiconductor & Computer Engineering
(No difference)
|
Revision as of 08:11, 16 December 2013
Crystal Well is the codename for the L4 cache, a discrete eDRAM silicon die, which is featured in the Iris Pro-equipped Haswell microprocessors. The eDRAM silicon die is separate from the main Haswell die but is package together with it. Crystal Well based processors started shipping in the third quarter of 2013.
Crystal Well is a true 128MB L4$ which could be utilized by the core itself, not just by the Iris Pro's Framebuffer. I.E. L3$ values that gets evicted go into the L4$. The L4$ caches bother GPU and CPU memory accesses; memory is partitioned between. If the GPU is disabled, such as when a discrete GPU is installed, the L4$ will be used exclusively by the CPU.
Intel has not disclose much technical specs regarding how the crystal well die communicates with the main die. Intel has stated that the cache is capable of delivering 100GB/s bandwidth (50GB/s in each direction).
Processors
| Crystal Well Processors | ||||||||
|---|---|---|---|---|---|---|---|---|
| Family | Number | Launch Date | Cores | Threads | Clock | Lithography | TDP | Die Size |
| Core i7 | 4950HQ | Q3 2013 | 4 | 8 | 2.4 GHz | 22 nm | 47 W | 37.5mm x 32mm |
| Core i7 | 4850HQ | Q3 2013 | 4 | 8 | 2.3 GHz | 22 nm | 47 W | 37.5mm x 32mm |
| Core i7 | 4750HQ | Q3 2013 | 4 | 8 | 2 GHz | 22 nm | 47 W | 37.5mm x 32mm |
| Core i7 | 4960HQ | Q4 2013 | 4 | 8 | 2.6 GHz | 22 nm | 47 W | 37.5mm x 32m |
| Core i7 | 4770R | Q2 2013 | 4 | 8 | 3.2 GHz | 22 nm | 65 W | 37.5mm x 32mm |
| Core i5 | 4570R | Q2 2013 | 4 | 8 | 2.7 GHz | 22 nm | 65 W | 37.5mm x 32mm |
| Core i5 | 4670R | Q2 2013 | 4 | 8 | 3 GHz | 22 nm | 65 W | 37.5mm x 32mm |