AT&T Mobility announced it has begun adding HSUPA technology to its two newest HSPA+-enabled smartphones, the Motorola Atrix and the HTC Inspire 4G. The two devices originally came to market with HSUPA disabled so subscribers' upstream throughput speeds have been capped at WCDMA speeds--384 Kbps. Both phones' built-in cellular modems are capable of supporting 14.4 Mbps in the downlink and 5.76 Mbps in the uplink. In most AT&T markets upstream speeds of around 1.5 Mbps are possible with HSUPA enabled. Article