Up to 30 times faster, based on evidence discovered in the latest software update. Poking through the iPhone software developers kit (SDK) version that Apple (AAPL) issued on Monday, programmers at
ZiPhone
discovered the word “SGOLD3” in the firmware that refers to the new device’s chipset.

AppleInsider
‘s Aiden Malley did some sleuthing and concluded this is a reference to an Infineon chipset, the S-GOLD3H (PDF), which, among other things, serves as the device’s cellular modem.

The first iPhone used a predecessor chip, the S-GOLD2, which supports AT&T’s EDGE network. EDGE is rated at up to 236.8 kbits over 4 timeslots, although benchmark tests found actual throughput on the original iPhone to be in the 50 to 90 kbps range (see here).

The new chip, which Infineon (IFX) describes as 3.5G, supports the so-called HSDPA (high-speed download packet access) protocol and promises throughput of up to 7.2 Mbps. That’s 30 times the maximum 236.8 kbits throughput of EDGE.

Wi-Fi, by comparison, offers data transfers ranging from 6.5 to 20 Mbps.

In other words, in areas where AT&T supports 3G, the new iPhone could offer cellular data throughput comparable to an 802.11b Wi-Fi network.