When it comes to LTE speeds, not all iPhone 7 devices are created equal.
A new study found performance differences between the Intel and Qualcomm modems used in the iPhone 7 and iPhone 7 Plus that can result in a serious dip in data speeds when owners encounter a weak signal.
[contextly_auto_sidebar] The iPhone 7 marks the first time Apple sourced modems from two different suppliers. The folks at CellularInsights decided to run both modems through a series of tests and discovered “unexplainable sharp dips in performance” of throughput on the Intel modem.
Which iPhone 7 modem do I have?
iPhone 7 customers who want to ensure they’re getting the fastest data speeds possible should buy the unlocked iPhone 7 variant, which comes with the Qualcomm MDM9645M modem. Verizon and Sprint models also include Qualcomm’s modem, which supports GSM/CDMA/WCDMA/TD-SCDMA/LTE networks.
AT&T customers are out of luck, though, because Apple chose to use the Intel XMM 7360 modem on those models with support for only GSM/WCDMA/LTE networks.
Intel versus Qualcomm modems in iPhone 7

Photo: CellularInsights
Depending on the situation, the Intel XMM 7360 modem performed as much as 30 percent slower than the Qualcomm MDM9645M modem on LTE bands. The max throughput of both modems was the same when researchers used a strong signal. But as soon as the signal strength weakened, Intel’s modem noticeably lagged behind Qualcomm’s.
CellularInsights also found that the Qualcomm modem is the only one with support for Ultra HD Voice. The feature is turned off, though, perhaps to even the playing field.