Screen flickers then phone dies while browsing over 3G

view story

http://forum.xda-developers.com – Phone is on stock ICS 4.0.3. It's 10 months old and only exhibited the issue just recently. While browsing using Dolphin over 3G the screen flickers while the page is still loading. The battery charge starts dropping quickly until the phone turns itself off. When the phone is turned on again after a few minutes the battery level is back at half. A check of the battery usage history shows a very steep drop followed by a rise back to mid levels even without charging. A full charge usually lasts 2-3 hours of continuous browsing. Changed to Chrome and it still flickers. I charged it while off ov (HowTos)