iPhone 3GS Upload Speeds Limited To 384 Kbps
Macworld has discovered that the while the new iPhone 3GS is capable of much faster download speeds, it’s upload speeds are comparatively not as fast as they were expected to be. The iPhone 3GS sports 7.2 Mbps HSDPA (downstream) which is quite a bit faster than the 3G’s 3.6 Mbps HSDPA, but it was assumed that Apple would also be increasing upstream speeds by finally adding HSUPA, bringing upload speeds to either 1.4 or 1.9 Mbps.
The RapidRepair tear down revealed this not to be the case. When they cracked open their iPhone 3GS, they found that it still only had a UMTS/HSDPA chip. While it had increased HSDPA speeds, it only supported UMTS, the earliest 3G upload protocol in the U.S., which is only capable of peak speeds of 384 Kbps.
This means that while download speeds with the 3GS are quite a bit faster (or will be in the U.S. when AT&T finishes their 7.2 network), upload speeds remain comparatively slow.
It is believed that this could be why Apple was reluctant to say much about the iPhone 3GS’s internal hardware when it was announced in June.