Which (non-Apple) laptops are shipping with 4266 MT/s LPDDR4X RAM?
DDR4 is always 64-bits. Two channel DDR4 is 128-bits. So right there, 2-channel x 64bits DDR4 is the same bus-width as the 8-channel x 16bits LPDDR4x.
With that being said, 8-channel LPDDR4x is more than most I've heard of. But its not really that much more than DDR4 configurations.
128-bit (2-channel) DDR4 at 3200 MT/s is 51 GB/s bandwidth.
4266 MT/s x 128-bits (8-channel) LPDDR4x is 68GB/s. An advantage, but nothing insurmountable.
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A Threadripper can easily run 4-channel 3200 MT/s (100GB/s). Xeons are 6-channel. GPUs are 500GB/s to 800GB/s tier. Supercomputer-GPUs (A100) and Supercomputer-CPUs (A64Fx) are 1000+GB/s.
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HBM2 has a MINIMUM speed of 250GB/s (single stack, 1024-bits), and often is run in x4 configurations for 1000GB/s. That's what "high bandwidth" means today. Not this ~68GB/s tier Apple is bragging about, but instead HBM is about breaking the PB/s barrier in bandwidth.
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But yes, I'll agree that Apple's 68GB/s configuration is an incremental (but not substantial) upgrade over the typical 40GB/s to 50GB/s DDR4 stuff being used today.
- Razer Book 13
- Dell XPS 13 9310 2-in-1
- MSI Prestige 14 EVO
- Intel's new whitebox laptop platform
I think I've read that there are now Ryzen laptops shipping with LPDDR4x as well. It's awesome that Apple is using ram with this much bandwidth, but it's not exclusive.
Its kind of ridiculous: LPDDR4 has been used in phones for years, but it took until this year before Intel / AMD added support for it. Ah well. This one is definitely on Intel / AMD's fault for being slow on the uptake.
DDR4 had largely the same power-draw of LPDDR3 (but was missing sleep-mode). So I think CPU makers got a bit lazy and felt like DDR4 was sufficient for the job. But LPDDR4x is leapfrogging ahead... the phone market is really seeing more innovation than the laptop / desktop market in some respects.