Tests show performance difference between iPhone 7 modems


Apple typically sources components from more than one vendor when possible. Sometimes these components result in some performance variation between devices. For example, we had slight differences in CPU performance between Samsung and TSMC chips. We also had differences in storage performance and LCDs properties.

With the iPhone 7 Plus, Apple is sourcing its LTE modem from Qualcomm and Inte,l and it appears there may be some advantages for Qualcomm iPhones. GSM-only devices (AT&T/T-Mobile) utilize an Intel modem and GSM/CDMA (Verizon/Sprint) utilize the Qualcomm modem.

Cellular Insights (via MacRumors):

Both iPhone 7 Plus variants perform similarly in ideal conditions. At -96dBm the Intel variant needed to have Transport Block Size adjusted as BLER well exceeded the 2% threshold. At -105dBm the gap widened to 20%, and at -108dBm to a whopping 75%. As a result of such a huge performance delta between the Intel and Qualcomm powered devices, we purchased another A1784 (AT&T) iPhone 7 Plus, in order to eliminate any possibility of a faulty device. The end result was virtually identical. [...]

At -121dBm, the Intel variant performed more in line with its Qualcomm counterpart. Overall, the average performance delta between the two is in the 30% range in favor of the Qualcomm

Basically it seems the problem is limited to conditions with weaker signals. Even then, it I'm not sure it's that big of a deal. The tests show antenna attenuation with lab conditions, which is interesting, but doesn't necessarily correspond directly to real-world performance. And that's not to say the Intel modem is slow on its own.

So, seems just another tiny detail for people who like to fret over things.