08-09-2019, 03:12 PM
@fire219 is mostly correct. PCIe 2.x is 5Gbps, but really only 4Gbps without overhead. So maximum of 16Gbps for data, using all 4 lanes. And yes, there really is 1Gbps overhead for a PCIe 2.x lane;
https://en.wikipedia.org/wiki/PCI_Expres...xpress_2.0
PCI 3.x and later, drop the overhead to an insignificant amount. So they can get away with PCIe 3's 8Gbps being double performance from PCIe 2's 5Gbps.
Of course, 16Gbps, (2GBytes ps), is still overwhelming fast compared to the eMMC or even SATA.
And from my reading, the SD controller is version 3.0, which is up to 104MBps, depending on the card installed. (If UHS-I or later card is used, that gets the 104MBps speed. Older cards get 50MBps or less.)
https://en.wikipedia.org/wiki/PCI_Expres...xpress_2.0
PCI 3.x and later, drop the overhead to an insignificant amount. So they can get away with PCIe 3's 8Gbps being double performance from PCIe 2's 5Gbps.
Of course, 16Gbps, (2GBytes ps), is still overwhelming fast compared to the eMMC or even SATA.
And from my reading, the SD controller is version 3.0, which is up to 104MBps, depending on the card installed. (If UHS-I or later card is used, that gets the 104MBps speed. Older cards get 50MBps or less.)
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Arwen Evenstar
Princess of Rivendale
Arwen Evenstar
Princess of Rivendale