My mate and I started playing ESO today. We both logged into the game, spent a good hour creating each of our characters and then hopped onto our characters. We spent quite a while exploring in Coldharbour and then eventually made our way out. (total time between Character creation and Coldharbour run around 1.5 to 2 hours) After that point, his game client started crashing frequently out in the open game world. Probably once every half hour or more often.
I loaded the game client onto his computer a couple weeks ago and ran one of my characters around and did a few quests as well as some combat to test and it seemed to work just fine. Now, however, the game crashes often and he seems to get an error report screen for each one. We have already tried the repair option on the launcher and it found no corrupt files. Not sure what else could be going on.
He is using a laptop with Windows 7 64 bit and an ATI Mobility Radeon HD 4670 card. We play LotRO every night and have played WoW (most recent expansion) and SWtOR on his computer and there are no significant issues such as crashing. We only seem to be having this issue on ESO in the open world.